Scores of people have reportedly been killed in the Syrian city of Homs, as government forces continued a relentless assault on the central city for a sixth day.

Activists said on Thursday that the bombardments centred on the neighbourhoods of Bab Amr, Khaldiyeh and al-Bayada.

Speaking to Al Jazeera from the city, activist Hadi al-Abdallah said 12 homes were targeted in Bab Amr, including three inhabited buildings.

"Three families were killed when buildings were shelled. The martyrs are women, men and children. The bodies are badly mutilated," he said.

In Khaldiyeh, Abdallah said one person was killed after government forces shelled the neighbourhood.

Activists say that hundreds of people have been killed and at least 570 injured since the army started its assault on the city last week.

"They targeted my neighbour’s house with rockets. I saw it with my own eyes," Omar Shakir, a resident in Bab Amr, told Al Jazeera.

"This is the sixth day in a row we are being shelled by rockets, by mortars, by every weapon," he said.

"[Syrian President] Bashar al-Assad is not a human...We are begging the world, please do something."

Shakir said residents of the neighbourhood were seeking safety on the ground floor of buildings as there were no underground shelters.

Reviving observer mission

Homs, Syria's third-largest city, has become the focus of both resistance and reprisal in the 11-month uprising as many areas have fallen under the control of increasingly bold opposition fighters who want to bring down the government.

In other parts of the country, activists reported clashes between Syrian troops and army defectors in Idlib, near the border with Turkey.

In eastern Deir al-Zor province, machinegun fire wounded dozens of people including women and children in Koriyeh, the UK-based Syrian Observatory for Human Rights said, adding that army reinforcements were being sent into the town.

As the violence grinds on, the international community is searching for new diplomatic approaches to stop the bloodshed.

Ban Ki-moon, the UN secretary-general, said on Wednesday that the head of the Arab League plans to send observers back into Syria and has raised the possibility of a joint mission with the UN.

Ban provided no specifics, but the idea appeared aimed at giving the regional group a boost after the league's earlier mission was pulled out of the country because of security concerns.

"In the coming days we will further consult with the council before fleshing out details," he said.

Ban also reiterated his "deep regret" over the council's inability to speak with one voice on the crisis in Syria.

Russia and China used their veto powers on Saturday to block a Security Council resolution backing an Arab League peace plan that called for Assad to step aside.

'Cold blood'

Ban said the lack of council unity had encouraged the Syrian government to step up its attacks on civilians.

"Thousands have been killed in cold blood, shredding President Assad's claims to speak for the Syrian people," Ban said.

"I fear that the appalling brutality we are witnessing in Homs, with heavy weapons firing into civilian neighbourhoods, is a grim harbinger of worse to come."

Earlier on Wednesday, Navi Pillay, the UN rights chief, issued an appeal for urgent international action to protect civilians.

"I am appalled by the Syrian government's wilful assault on Homs, and its use of artillery and other heavy weaponry in what appear to be indiscriminate attacks on civilian areas in the city," a statement from the Office of the UN High Commissioner for Human Rights said.

In another diplomatic development, Ahmet Davutoglu, the Turkish foreign minister, announced plans for an international meeting.

"We are determined to establish a broad-based forum to promote international understanding with all countries concerned" with developments in Syria, Davutoglu said in a televised interview on Wednesday.

A senior EU official in Brussels said the 27-nation bloc could soon impose harsher sanctions against Syria.

The official said new measures could include bans on the import of Syrian phosphates, on commercial flights between Syria and Europe, and on financial transactions with the country's central bank. The European Union imports 40 per cent of Syria's phosphate exports.

Violence continues to escalate across Syria, as deadline set by the Arab League approaches for the government to end its deadly crackdown on anti-government protesters.

The deadline set by the 22-member bloc expires on Saturday, a day after Syrian security forces killed at least 17 civilians, including two children.

Members of the self-styled Free Syrian Army were reported to have killed three members of the security forces.

The latest violence came as international pressure mounted on Bashar al-Assad's rule.

Turkey and the US both raised the spectre of civil war, as thousands of protesters took to the streets on Friday to urge nations to expel Syrian ambassadors, defying a massive security presence.

Syria has agreed "in principle" to allow dozens of Arab observers into the country to monitor implementation of a peace deal agreed earlier this month, but with conditions.

The Arab League said it was examining a Syrian request to make changes to a proposal to send 500 observers to Damascus.

However, critics said Syria is only stalling, trying to defuse international pressure while continuing its violent crackdown on an eight-month-old uprising which the UN estimates has killed more than 3,500 people.

Syria has been told by its Arab peers to end the crackdown against protesters by midnight local time (22:00 GMT on Saturday) or risk sanctions, and the Arab League has already suspended it from the 22-member bloc.

Iran called the suspension "a historic mistake" that would in itself cause civil war.

Opposition talks

In another development, William Hague, the British foreign minister, announced on Friday that he would meet Syrian opposition representatives in London next week.

The Syrian opposition members would also meet senior aides of David Cameron, the UK prime minister, at his Downing Street office, the foreign ministry said on Friday.

It said that Frances Guy, the former British ambassador to Lebanon, had been appointed to co-ordinate relations with the Syrian opposition.

The delegation would include members of the opposition Syrian National Council and the National Co-ordination Committee for Democratic Change, in meetings expected to take place on Monday, a Foreign Office source said.

"We have been having regular contacts with a variety of figures in the Syrian opposition for several months. We are now intensifying these," the Foreign Office said.

Increased pressure

For its part, France has called on the UN Security Council to act against Assad's government, saying the time has come to strengthen sanctions against Syria.

"We must continue to exert pressure," Alain Juppe, the French foreign minister, said at a joint news conference on Friday with Ahmet Davutoglu, the Turkish foreign minister, in Ankara.

Davutoglu also increased pressure on Syria, saying that "if there's no response to the latest attempt of the Arab League, which has Turkey's support, then certain measures must be taken".

Vladimir Putin, the Russian prime minister, called for restraint over the crisis.

"We are calling for restraint and caution. This is our position," Putin said, a day after his foreign minister had likened the situation in Syria to a civil war.

Hillary Clinton, the US secretary of state, warned on Friday of the possibility of a civil war in Syria that either is
directed or influenced by Syrian army defectors.

"I think there could be a civil war with a very determined and well-armed and eventually well-financed opposition that is, if not directed by, certainly influenced by defectors from the army," Clinton told the US network NBC.

"We're already seeing that, something that we hate to see because we are in favour of a peaceful ... protest and non-violent opposition."

'Villages shelled'

Activists said on Friday that Syrian troops had shelled two northern villages overnight after an attack by army defectors on forces loyal to Assad, in the first report of such an incident during the eight-month uprising.

Eight villagers were injured when tank shells and heavy mortars fell for three hours on Tal Minnij and Maarshamsheh and surrounding farmland, activists told the Reuters news agency.

"Hundreds of families have left. Electricity and internet services have been cut off," said one activist who gave his first name as Raed.

Army defectors had earlier attacked a building housing security forces near army depots in the Wadi al-Deif area on the edge of the town of Maarat al-Numaan, 290km north of Damascus, the activists said.

The town, on the Damascus-Aleppo highway, has seen regular street protests demanding Assad's removal and raids by security forces to put down the demonstrations.

In the last few weeks, residents say a growing number of army defectors have been defending Maarat al-Numaan and attacking army patrols and roadblocks.

The authorities blame the violence on foreign-backed armed groups who they say have killed more than 1,100 soldiers and police.

Syria's official news agency said troops carried out a "qualitative operation" in the region, arresting 58 wanted people and seizing rifles and bomb detonators.

The agency said eight "of the most wanted terrorists" were arrested on Thursday in the central city of Homs, where tanks have been deployed.

'Bye bye Gaddafi... It's your turn next', Syrian protesters in Lebanon tell Assad [Reuters]

Deaths have been reported during the latest protests in Syria, including up to 16 in the flashpoint central city of Homs,
the opposition Local Co-ordination Committees announced.

Two people were shot dead on Friday in Homs by security forces manning a checkpoint, while 14 more were killed as they participated in mass protests, activists said.

Another civilian died when security forces opened fire on a funeral procession in the southern Deraa region, one of the focal points of opposition to Syrian President Bashar al Assad's government and two more people died in the central province of Hama, according to the observatory.

Some protesters drew inspiration on Friday from the death of Muammar Gaddafi, the toppled Libyan leader, as the country's opposition called for fresh protests in support of the Libyan people and against Assad's government.

"Gaddafi is gone, your turn is coming Bashar," protesters shouted on Friday in Hama. "Our souls, our blood, we sacrifice for you, Libya!" they chanted.

Syria's uprising has proved resilient over the past seven months in the face of a fierce crackdown estimated to have killed more than 3,000 people according to UN estimates, but it has shown some signs of stalling in recent weeks.

In Qusair, near the Lebanese border, Syrian forces closed all mosques to prevent people from gathering. The weekly protests usually begin as Syrians pour out of mosques following Friday afternoon prayers.

Although the mass demonstrations in Syria have shaken al Assad's government, the opposition has made no major gains in recent months, it holds no territory and has no clear leadership.

But Gaddafi's demise has raised hope among protesters that Assad could be driven out from power by an "Arab Spring"-uprising.

Some held signs linking Assad's fate to those of other deposed Arab leaders. Tunisia's Zine el Abidine Ben Ali has been driven to exile, and Egypt's Hosni Mubarak is in prison and facing charges of complicity in the deaths of more than 800 protesters in his country's uprising.

"Ben Ali fled, Mubarak is in jail, Gaddafi is killed, Assad...?" read one banner.

Syria's protesters have taken other cues from their Libyan counterparts.

Syria's opposition formed a national council, in imitation of Libya's National Transitional Council, hoping they could form a united front against Assad that Syrians and the international community could rally behind.

Some protesters also called on their compatriots to take up arms and invited foreign military action, hoisting signs that say "Where is NATO?" and urging the world to come to Syria's aid.

For the most part, Syrian opposition leaders have opposed foreign intervention.

Dozens of people have been reported killed across Syria, a day after the Arab League announced it was encouraging dialogue between Bashar al-Assad's government and the opposition.

The Local Co-ordination Committees (LCC), an activists' network, said 24 people were killed on Monday in Homs, which has been one of the centres of the protests against President Assad's 11-year rule.

The group said troops also killed four civilians in Idlib province in the northwest, three in the city of Hama, and one in Deraa.

Separately, the UK-based Syrian Observatory for Human Rights (SOHR) reported the deaths of 11 soldiers, four of them in a bombing.

"Gunmen suspected of being army defectors blew up a bomb by remote control as an army vehicle passed by Ehssem in the countryside of the [northwestern province of Idlib], killing an officer and three soldiers, and wounding others," Rami Abdel Rahman, the SOHR director, told the AFP news agency.

Earlier, SOHR reported that seven soldiers were killed in clashes with assailants suspected of being army defectors in Homs province.

Syrian authorities say "armed terrorist groups" are operating in Homs, killing civilians and prominent figures. Foreign reporters are largely banned from Syria, making independent confirmation of reports difficult.

'Doctors arrested'

Elsewhere, the LCC said it had documented the arrests of 25 doctors and pharmacists from private clinics and hospitals in the past few weeks.

The group said 250 doctors and pharmacists have been arrested since the start of the uprising.

The accusation that authorities are targeting doctors and raiding hospitals in search of wounded protesters has been made before by leading international human rights groups.

Last month, US-based Human Rights Watch said Syrian security forces "forcibly removed" patients from a hospital and prevented doctors from reaching the wounded during a military siege in Homs.

Monday's developments follow the Arab League's announcement a day earlier that it planned to bring together Syria's government and opposition groups to seek ways to end the violence.

"We will call all of the parties of the opposition and government to hold a dialogue within 15 days," Nabil el-Araby, the group's secretary-general, said after an emergency meeting of Arab foreign ministers in the Egyptian capital on Sunday.

But Youssef Ahmad, Syria's ambassador to the Arab League, aired his country’s reservation to the Arab League's resolution, the Syrian state news agency, SANA, reported.

Ahmad said his country will not hold talks in Cairo, affirming that Syria is an independent and sovereign country led by a legitimate authority, and that "any national dialogue can only be held in Syria".

Syrian state media says security forces have withdrawn from the city of Deir ez-Zor and key areas in Latakia following operations that anti-government activists say have left dozens dead.

Convoys of army vehicles were seen leaving Deir ez-Zor after the military cleared the area of "armed terrorist gangs", SANA, the state-run news agency, reported. Footage showed pictures of crowds chanting and cheering as the soldiers left.

But on Wednesday, Ahmet Davutoglu, the Turkish Foreign Minister said Syrian troops were still in the city. Witnesses also said troops have not yet withdrawn.

"We stress the necessity that the army withdraws and ends the military campaign. I can confirm that Deir ez-Zor is still witnessing problems and the army is in Deir ez-Zor and other towns," he said, speaking at a news conference in Istanbul with his Jordanian counterpart Nasser Judeh.

Witnesses on the ground also disputed the government's announcements, Al Jazeera's Nisreen el-Shamayleh said on Wednesday, reporting from Ramtha, on the Syria-Jordan border.

"[They said] a lot of the tanks have been moved to other suburbs on the outskirts of Deir ez-Zor, but did not exit completely ... They basically provide these accounts that challenge these statements from the Syrian government."

Activists also told Al Jazeera that gunfire was heard near Freedom Square after Ramadan prayers on Tuesday night, where two people were reported to be killed.

On Tuesday, the Syrian Observatory for Human Rights (SOHR) reported that one person was killed when security forces opened fired to disperse an anti-government protest in the city when "hundreds of people" marched in Takaya street.

Residents said tanks were still present at the outskirts of Deir ez-Zor and that troops were raiding houses looking for wanted dissidents. Activists say at least 32 people have died since troops seized control of the city last Wednesday.

'End' of operation

Meanwhile, Syria's interior ministry said security forces had completed their operation in the al-Ramel al-Janoubi neighbourhood of the coastal city of Latakia, which had been subjected to a four-day assault that activists say has left at least 36 people dead.

Brigadier General Mohammad Hassan al-Ali said al-Ramel al-Janoubi, which houses a Palestinian refugee camp, "is recovering and the citizens are practicing their normal life that was spoiled by the acts of the terrorist groups," SANA reported.

However, "activists told us that on Tuesday night and early on Wednesday morning, specifically at 8am local time on Wednesday, heavy gunfire was heard across neighbourhoods in Latakia and that two Palestinians were killed on Tuesday night," Shamayleh reported.

Hundreds of security services also raided homes in the the city on Wednesday, the AFP news agency reported.

The SOHR told the AFP that more than 700 members of the security services took part in the operation in the southern district of Ramel, arresting people on lists.

"Heavy gunfire continued in most opposition neighbourhoods" overnight, the group said.

In Jabal al-Zawya, a village in Idlib province near the border with Turkey, security forces shot dead a man standing on his balcony, the SOHR told AFP.

Dawn raids

Security forces in Damascus carried out dawn raids in Rukn Eddin district, known to be a predominantly Kurdish area, where electricity was cut off, and arrested dozens of activists. Dozens of others were arrested overnight on the outskirts of the capital.

el-Shamayleh said activists confirmed that dozens were arrested in Damascus and that two huge protests took place in two Palestinian refugee camps in the capital to demonstrate against the shelling of al-Ramel refugee camp in Latakia.

On Wednesday, Switzerland widened sanctions against the Assad regine, adding 12 more individuals to a
list of key players under financial embargo and travel restriction, the AFP reported.

Western diplomats said the UN's top human rights body is likely to hold an urgent meeting next week to discuss the escalating crackdown in Syria, according to the AP news agency.

Syria's key regional ally Iran warned on Tuesday that any Western intervention in the "internal affairs" of Damascus would stoke "public hatred" in the region. 

The crackdown in Syria has escalated since the beginning of the fasting month of Ramadan, when nightly prayers became the occasion for more protests against Assad and 41 years of Baathist rule.

Syrian tanks again opened fire on besieged districts in the northern port city of Latakia, residents said, in the fourth day of a military assault aimed at crushing protests against President Bashar al-Assad.

Troops were removing bodies from the main square in the city on Tuesday, and some areas were on lockdown, sources told Al Jazeera.

A resident of the al-Ramel al-Janoubi neighbourhood, who called himself 'Ismail', told Al Jazeera that random shelling from gunboats and tanks continued in Latakia. He said five people had already been killed, and snipers were stationed around the city, shooting at anyone who ventured into the streets.

"What's happeninig [in Latakia] is really severe. Shooting is still there and the buildings are occupied by others. The moment they see anything moving they will shoot it," Ismail said.

"Yesterday we had a lot of problems in this area, a daughter was killed and her father was killed... No one is safe in this area."

Al Jazeera cannot independently verify reports from Syria because of restrictions on reporting in the country.

'Thousands' arrested

Other activists have told Al Jazeera that "a large group of security forces dressed as civilians were chanting 'We will sacrifice our blood and our souls for you Bashar al-Assad'," our correspondent Nisreen el-Shamayleh said, reporting from the Jordanian side of the Syria-Jordan border.

She added that "thousands" who were arrested in Latakia on Monday were still being held at the Sports City Stadium there, according to witnesses.

"They are still being held captive, have been stripped of their IDs, have not been let out, they have had to stay overnight at the stadium, and have not been given food or water."

The Syrian Revolution Coordinating Union, a grassroots activists' group, said at least six people were killed in Latakia on Monday, bringing the civilian death toll there to 35, including a two-year-old girl, Reuters reported.

A resident told the Reuters news agency that heavy machine gun fire, explosions and intermittent tank fire were heard in the neighbourhoods of al-Ramel, the site of a Palestinian refugee camp, and al-Shaab on Tuesday morning.

Meanwhile, a senior official in the Palestine Liberation Organisation spoke out about the violence used against Palestinian refugees.

"The shelling is taking place using gunships and tanks on houses built from tin, on people who have no place to run to or even a shelter to hide in," Yasser Abed Rabbo, the PLO secretary general, told Reuters. "This is a crime against humanity."

Escalating crackdown

The crackdown has escalated since the beginning of the Muslim fasting month of Ramadan, when nightly prayers became the occasion for more protests against Assad and 41 years of Baathist rule.

"We hope for international intervention, and we need a military intervention, because we need to stop the mass killing. We need to stop the acts and we need to sort it out," Ismail told Al Jazeera.

Residents told Al Jazeera on Monday that the army used heavy machine guns and tanks, and forced thousands of residents - including many Palestinian refugees - to flee their homes. Many had been rounded up in the sports stadium as they attempted to escape the city.

Chris Gunness, a spokesman for the UN agency for Palestinian refugees, said 5,000 to 10,000 residents of a Palestinian refugee camp in the al-Ramel area of the city had been fleeing after the camp came under fire.

El-Shamayleh said residents there called the assault the "most atrocious attack" since protests against Assad's government began five months ago.

"People are trying to flee but they cannot leave Latakia because it is besieged. The best they can do is to move from one area to another within the city," a witness told Reuters.

Diplomatic pressure

Meanwhile, in the central city of Homs, a witness told Al Jazeera that 12 people were killed after security forces fired on people after Ramadan prayers on Monday night.

Activists also reported random arrests in the capital, Damascus.

Syria faces mounting diplomatic pressure to end its crackdown on protests, with Ahmet Davutoglu, the Turkish foreign minister, on Monday threatening Damascus with unspecified "steps" if it failed to do so.

Davutoglu said the bloodshed must end "immediately and without conditions or excuses".

"If the operations do not end, there would be nothing more to discuss about steps that would be taken," he said, without saying what that action could include.

Jordan also urged Syria to stop violence and start implementing reforms.

"Prime Minister Maaruf Bakhit today telephoned his Syrian counterpart Adel Safar and told him that violence must stop immediately," the state-run Petra news agency reported.

"Bakhit said Syria should listen to reason and start implementing reforms."

The military has denied reports that gunboats seen off the coast of Latakia have been used in the assault [YouTube]

Syrian troops have kept up their assault on the coastal city of Latakia for a third day, reportedly killing three people.

Residents told Al Jazeera that the army was using heavy machine guns and tanks, and had rounded up thousands of people in a sports stadium in the city on Monday.

"As of 10GMT, the army instructed all residents in southern and southeastern Latakia to evacuate", Al Jazeera's Nisreen El-Shamayleh, reporting from the Jordanian side of the Jordan-Syria border, said.

"According to activists, most people started fleeing to the heart of the city and there Syrian troops arrested thousands.

"They transported them on buses to the sports city stadium and there they're being held captured, stripped of their IDs and mobile phones."

The Syrian Revolution Co-ordinating Union, a grassroots activists' group, said three people were killed by security forces on Monday, bringing the total killed since Saturday to at least 31 civilians

The UK-based Syrian Observatory for Human Rights (SOHR) said one of the three was killed after troops opened fire as a group of fleeing residents approached a checkpoint in the Ein Tamra district of Latakia.

"People are trying to flee but they cannot leave Latakia because it is besieged. The best they can do is to move from one area to another within the city," a witness told Reuters.

Turkey threat

Meanwhile, the Turkish foreign minister, Ahmet Davutoglu, urged Syria to immediately end its deadly crackdown, threatening it with unspecified "steps" if it fails to do so.

Davutoglu said the bloodshed must end "immediately and without conditions or excuses."

"If the operations do not end, there would be nothing more to discuss about steps that would be taken," he said, without saying what that action could include.

The worst-hit area of Latakia is the al-Ramel neighbourhood, which has seen persistent protests since the uprising began. The area also houses a Palestinian refugee camp.

Chris Gunness, a spokesman for the UN agency for Palestinian refugees, said 5,000 to 10,000 residents of the camp had been fleeing after it came under fire. 

The government has justified its crackdown on the city by saying it is dealing with "terrorist" gangs. 

On Sunday, official news agency SANA said troops were pursuing "gunmen using machine guns, hand grenades and bombs who have been terrorising residents in the al-Ramel district'.'

A military source on Monday denied reports that the army had been using gunboats in the offensive, saying ships seen off the coast were carrying out routine tasks of protecting the coast and preventing weapons smuggling.

Elsewhere in the country, troops backed by tanks reportedly entered several towns in the central province of Homs, a flashpoint of demonstrations.

"The community of Holeh is under siege ... The army is carrying out raids and arrests under the cover of heavy gunfire," the SOHR said.

The group said a sniper had killed an elderly man.

Al Jazeera is unable to independently verify reports because of restrictions on reporting in Syria.

'Assad offered asylum'

Meanwhile, neighbouring Jordan on Monday urged Syria to stop violence and start implementing reforms.

"Prime Minister Maaruf Bakhit today telephoned his Syrian counterpart Adel Safar and told him that violence must stop immediately," the state-run Petra news agency reported.

"Bakhit said Syria should listen to reason and start implementing reforms."

Andreas Peschke a foreign ministry, spokesman said reports of the assault on Latakia by tanks and navy gunboats gave a new reason to send a stronger message and increase EU sanctions.

"This current use of violence cannot be justified morally or under international law in any way," he said. "We are advocating for the UN Security Council to address the Syria issue again this week."

Earlier on Monday, Spain's El Pais newspaper reported that Madrid sent a special envoy to Damascus last month to convince Assad to accept a plan to go into exile with his family.

The government was also "ready to offer asylum to Assad and his family in Spain," the country's leading daily said.

"My impression is that [Assad] will not compromise on anything substantial," envoy Bernardino Leon said on his return, El Pais reported. "My [Syrian] interlocutors were totally detached from reality."

At least 25 people have been killed and many others injured after Syrian warships and tanks opened fire on the port city of Latakia, activists said.

A resident in al-Ramel, one of the neighbourhoods which came under attack on Sunday, said at least three gunboats were taking part in the offensive.

"Many homes have been destroyed and the shabiha have broken into shops and businesses," he said, referring to pro-government thugs.

The security forces appear to be intent on crushing dissent in the neighbourhood, which has seen large anti-government protests since the Syrian uprising began in mid-March.

The National Organisation for Human Rights in Syria (NOHRS) provided a list of 26 victims, including two Palestinian men from the Ramel refugee camp in southern Latakia.

"Poor communications make it impossible to confirm numbers of those killed and injured," Gunness said in a statement.

Rami Abdul Rahman, head of the UK-based Syrian Observatory for Human Rights, said one of the dead was a two-year-old girl who was in a car with her father when security forces at a checkpoint opened fire.

The assault on Latakia began on Saturday, when tanks and armoured personnel carriers rolled into al-Ramel amid intense gunfire. Five people were reportedly killed in the offensive. 

'Pursuing gunmen'

State-run news agency SANA said troops were pursuing "gunmen using machine guns, hand grenades and bombs who have been terrorising residents in al-Ramel district".

The agency denied reports the area was being targeted from the sea. It quoted a health official in Latakia as saying two law enforcement officials were killed.

Elsewhere in the country, NOHRS said two people had been killed in Homs, one in Hama and one in Idlib.

Around the capital, Damascus, "security forces entered Saqba and Hamriya in great numbers and launched a campaign of arrests," according to the Syrian Observatory for Human Rights.

Canada said on Saturday that it had expanded sanctions on Syria to protest against the government's brutal crackdown on demonstrations.

The new sanctions include travel bans on four officials and freezing the assets of the state-run Commercial Bank of Syria, and Syriatel, the country's largest mobile phone company.

The US imposed sanctions on the two firms earlier in the week, and has joined European allies in sanctioning top officials close to President Bashar al-Assad.

'Violence must end'

Canada's sanctions came after US President Barack Obama spoke with the leaders of Saudi Arabia and the UK and all three called for an immediate end to the Syrian government's crackdown on protests.

Obama and Saudi King Abdullah "expressed their shared, deep concerns about the Syrian government's use of violence against its citizens," the White House said in a statement.

"They agreed that the Syrian regime's brutal campaign of violence against the Syrian people must end immediately, and to continue close consultations about the situation in the days ahead."

Similar language was used in a statement after a separate Obama conversation with British Prime Minister David Cameron.

Tens of thousands of people rallied in cities across the country on Friday in protest against the government and at least 17 people were reported killed.

The protests have grown dramatically over the past five months, driven in part by anger over the government's bloody crackdown in which rights groups say at least 2,000 civilians have been killed across the country.

The government has justified its crackdown by saying it is dealing with terrorist gangs and criminals who are fomenting unrest.

A Latakia resident speaking to Al Jazeera on Saturday rejected the government's claims.

"There are no armed gangs here," he said. "We have been demonstrating peacefully for the last three months."

Syrian authorities have expelled most independent journalists since the five-month-old uprising against Assad began, making it difficult to verify reports from both sides.

Syrian tanks stormed two northwestern towns near the border with Turkey, expanding its military offensive to crush protests, local residents said, a day after Ankara pressed Syrian President Bashar al-Assad to end killings of civilians.

The Syrian Observatory for Human Rights (SOHR) said at least one woman was killed and 13 people injured on Wednesday when 12 tanks and armoured vehicles, entered the towns of Taftanaz and Sermin, around 30km from the border with Turkey.

In Homs at least 16 people have been killed by security forces, reports from activists said.

Omer Onhon, the Turkish ambassador, visited Hama on Wednesday and said that tanks were moving out of the city ten days after the army stormed in.

Forty personnel carriers decked with Syrian flags rolled out of Hama with soldiers chanting slogans praising embattled Assad, said a journalist from the AFP news agency who visited the city on a tour organised by the authorities.

However, witnesses told Al Jazeera that after Onhon's visit to Hama, where he was told military operations had ended, Syrian army forces moved back into the town.

Syrian troops also seized control of the eastern flashpoint city of Deir ez-Zor on Wednesday following intense shelling and gunfire, an activist said. The city has been under attack by Assad's forces for four days.

"They are shooting anything that moves," the activist said, speaking to the AP news agency by telephone on condition of anonymity for fear of reprisals.

"The situation is terrible. Bakeries and pharmacies are closed, while food and baby formula are scarce."

In the town of Albukamal, located in the province of Deir ez-Zor, the security forces and members of the Shabiha armed group carried out a campaign of mass arrests early Wednesday morning, detaining at least 35 people, Avaaz, an international human rights organisation, said.

Syrian troops also launched another operation in three suburbs of the capital Damascus, the London-based SOHR.

International pressure

With the situation growing bleaker in the country, the international community has stepped up pressure on Assad.

Envoys from India, Brazil and South Africa were due in Damascus on Wednesday and were expected to have held talks with Walid al-Muallem, the foreign minister.

The US says it is watching the situation in Syria with horror, and the US Department of the Treasury issued sanctions on the commercial bank of Syria, and its Lebanon-based subsidiary, as well as Syriatel, the largest mobile phone operator.  

On Tuesday, Ahmet Davutoglu, Turkey's foreign minister, urged Assad to end the killings, while US officials said the Obama administration was preparing to explicitly demand his departure.

Assad has largely shrugged off the pressure.
 
Syria's state-run news agency said he told Davutoglu the government will relentlessly fight "terrorist groups" - a term Syrian authorities often use for government opponents even though most of those killed are said to be unarmed, peaceful protesters.

Rights groups say about 1,700 people have been killed since March, and an aggressive new military campaign that began a week ago has killed several hundred.

  

The Turkish foreign minister has met Syrian President Bashar al-Assad in Damascus, as Syrian security forces continued their military assault against protesters across the country.

Ahmet Davutoglu was to deliver a "strong message" to the president during his visit to the Syrian capital, Turkey said ahead of Tuesday's visit.

Turkey, formerly Syria's close ally and trade partner, has grown increasingly alarmed by the security forces' use of force in the country's anti-government protests, which activists say has claimed about 2,000 lives.

As Davutoglu met Assad and the Syrian foreign minister, Walid al-Muallem, the army intensified its assault on several towns in the east of the country and in the northern Idlib province, which borders Turkey.

A rights group said 17 civilians were killed in the eastern city of Deir ez-Zor, and two others in Idlib province.

"At least 15 people were killed in different parts of Deir ez-Zor which has been raided by tanks and vehicles mounted with machine guns," the UK-based Syrian Observatory for Human Rights (SCHR) said in a statement. quoting activists at the scene.

"A woman and a young man shot [earlier in the day] died of their wounds."

A resident said armoured vehicles had been shelling the al-Hawiqa district heavily.

"Private hospitals are closed and people are afraid to send the wounded to state facilities because they are infested with secret police," the resident told Reuters news agency.  

He said at least 65 people had been killed since tanks and armoured vehicles entered the provincial capital on Sunday.

The SCHR said around a dozen tanks and other armoured vehicles had attacked the Binnish and Sirmeen areas of Idlib.

Asked why Binnish was stormed, a resident who had fled the town told Reuters: "The whole town has been joining in night rallies after Ramadan prayers."

The Local Co-ordination Committees said the town of Sirmeen was attacked from three sides, with troops carrying out house raids and arbitrary arrests.

Tanks were also deployed in and around the city of Idlib, following big demonstrations there, the activists said.

Hama deaths reported

Up to five civilians were later also during raids on villages around the besieged city of Hama on Tuesday, local activists said.

The Syrian Revolution Co-ordinating Union said five bodies had been taken to the Jwash hospital in the town of Tibet al-Imam north of Hama, including two girls from the same family, six-year old Afra Mahmoud al-Kannas and 11-year old Sana Ahmad al-Kannas.

Al Jazeera could not independently verify the reports since most foreign journalists have been barred from entering Syria.

The Syrian Observatory says more than 2,050 people, including almost 400 members of the security forces, have been killed since the uprising began.

Diplomatic action

Envoys from India, Brazil and South Africa are going to Damascus to press Assad to end the violent crackdown on a five-month old uprising.

India's UN ambassador Hardeep Singh Puri told reporters the three countries would be "calling for restraint, abjuring violence, [and] promoting reform, taking into account the democratic aspirations of the people.''

Officials said country's representatives were to meet "high-level'' Syrians on Wednesday.

Assad's government disputes the toll and blames a foreign conspiracy for the unrest. But those claims have been dismissed by most of the international community, with world leaders ramping up its condemnation of the security forces' actions in recent days.

Saudi Arabia, Kuwait and Bahrain on Monday recalled their ambassadors from Damascus amid mounting pressure from the Arab world.

Qatar withdrew its ambassador from Damascus and closed its embassy in July after Assad loyalists attacked the embassy compound amid protests against Doha-based Al Jazeera's coverage of the uprising.

Meanwhile, Assad replaced his defence minister, Ali Habib, on Monday with illness cited as the official reason.

State television reported that the Christian chief of staff, General Daoud Rajha, was to take up the post.