Details of the case against the four suspects were published by the STL on Wednesday [STL website]

Lebanese authorities must do more to apprehend four suspects wanted over the assassination of Rafiq al-Hariri, the country's former prime minister, the head of the UN special tribunal investigating the case said.

Antonio Cassese, the president of the Special Tribunal for Lebanon, ruled on Thursday that the tribunal's indictment against the four should be publicly advertised before a decision is made on whether to prosecute them in absentia.

Cassese said efforts by Lebanese authorities to arrest the suspects had been "reasonable", but urged them to intensify their hunt for the accused.

"It must be emphasised, however, that the report submitted by Lebanon on 9 August 2011 does not end Lebanon's continuing obligation to assist the Tribunal in searching for, serving, arresting, detaining and transferring the accused," Cassese said.

The report handed into the judge by the Lebanese authorities stated that they had been unsuccessful in efforts to apprehend Mustafa Amine Badreddine, Salim Jamil Ayyash, Hussein Hassan Oneissi and Assad Hassan Sabra.

The newly published order detailed the efforts made by the Lebanese authorities in their search. “I conclude that the efforts made by Lebanon, as detailed in the report submitted on 9 August 2011, have been reasonable….The Lebanese authorities have, inter alia, conducted surveillance, interviewed alleged associates, visited localities where the accused were believed to have connections, met with the majors of those localities, and canvassed the neighbourhoods for people with information about the accused,” stated the judge in his report.

Hariri was killed, along with 21 others, on the 14 February 2005 in a massive explosion that rocked Beirut.

Hezbollah dismiss reports

The STL lifted confidentiality restrictions surrounding the case on Wednesday, publishing the full text of the indictment and other details concerning the investigation.

Hassan Nasrallah, secretary general of Hezbollah, dismissed the recently published reports on Wednesday, stating that there was 'no direct evidence' against them.

Nasrallah accused the tribunal of being unscientific, saying: "When you read the text released by the tribunal, you will not find any substantial evidence, not a single piece of direct evidence is included."

"The only thing the tribunal relies on in is the mobile phone records, and even that is circumstantial. It doesn't even prove that any of these alleged suspects made any of these calls or even owned these phones."

The STL, which was established by the United Nations in 2007 to investigate the killing, has had a polarising effect on Lebanese domestic politics, dividing the country into two distinct camps; those who believe the STL is pushing forward a political agenda to bring down Hezbollah, and those who believe that the court is the only institution that will be able to objectively rule on the killing.

Hezbollah and its cabinet allies have dominated Lebanon's coalition government since members of a coalition led by Saad Hariri, Rafiq al-Hariri's son, quit amid controversy over the STL investigation.

All four suspects are members of Hezbollah, although the group has denied any involvement in the assassination, saying that the investigation leading up to the indictments had been politically motivated and ignored the possibility of investigating other suspects.

The Special Tribunal for Lebanon (STL) has lifted confidentiality restrictions on an indictment issued in its investigation into the killing of Rafiq al-Hariri, the former Lebanese prime minister blown up by a car bomb in 2005.

Wednesday's move means details of the case against four men named as suspects by the tribunal in June and subject to arrest warrants can be revealed for the first time. The UN-established tribunal said in a statement it had taken the step in order that the case could "proceed to trial".

The four men named by the STL - Mustafa Amine Badreddine, Salim Jamil Ayyash, Hussein Hassan Oneissi and Assad Hassan Sabra - are all members of Hezbollah.

The newly released documents reveal details of the four suspects' phone records and a complex communications network they are alleged to have used in co-ordinating and carrying out the February 2005 assassination in which 21 other people also died.

"This order will finally inform the public and the victims about the facts alleged in the indictment regarding the commission of the crime that led to charging the four accused," tribunal prosecutor Daniel Bellemare said in a statement.

Investigators admit that the evidence gathered is largely circumstantial, primarily because it is based predominantly on phone networks. Using Call Data Records, the prosecution worked with the method of 'co-location', which basically meant that cell phone activity was recorded in accordance to its geographical proximity to certain cell-towers.

Rami Khouri, director of the Issam Fares Institute for Public Policy and International Affairs as well as editor at large of Lebanon's Daily Star newspaper, told Al Jazeera that at first glance, the information published appears to be quite persuasive.

"The level of detail is quite compelling," he said. "Everyone has been waiting for this to come out to decide if this is a credible process or a political and bias process. The evidence now shows there is an incredible amount of detail, and this sets the stage for some dynamic and turbulent times ahead."

Kamel Wazni, a political analyst in Beirut, pointed out that the evidence released is entirely circumstantial. "This is based entirely on phone networks," he told Al Jazeera. "This doesn't prove those people are behind it. Hizbullah sees these claims as a a fabrication, and there is no concrete evidence that links them to the assassination."

He went on to point out that in the past Hassan Nasrallah, secretary-general of Hezbollah, has repeatedly produced video footage and evidence highlighting Israel's involvement in the country, and linked that with the increased number of spies who have been caught recently spying for Israel.

"I think Hezbollah presented stronger evidence on Israeli infiltration in Lebanese networks, but this has not been taken into consideration by the STL," said Mr Wazni.

The STL, which was established by the United Nations in 2007 to investigate the killing, has had a polarising effect on Lebanese domestic politics, dividing the country into two distinct camps; those who believe the STL is pushing forward a political agenda to bring down Hezbollah, and those who believe that the court is the only institution that will be able to objectively rule on the killing.

Hezbollah and its cabinet allies have dominated Lebanon's coalition government since members of a coalition led by Saad Hariri, Rafiq al-Hariri's son, quit amid controversy over the STL investigation.

Hezbollah has denied any involvement in the assassination, saying that the investigation leading up to the indictments had been politically motivated and ignored the possibility of investigating other suspects.

Hassan Nasrallah, the leader of Hezbollah, has repeatedly dismissed the tribunal as a US-Israeli conspiracy against his movement and says the suspects will not be handed over to face trial.