The U.N. inquiry into the assassination of former Lebanese Prime Minister Rafik Hariri has now identified suspects and witnesses and found possible links to 14 other murders or attempted murders in Lebanon in the last two years, the chief investigator said Tuesday.

Belgian prosecutor Serge Brammertz said his investigation has reached "a critical stage." Investigators are looking at numerous motives including assassination by an extremist group because of Hariri's links to other states in the region and in the West, an attempt to prevent his possible success in May 2005 elections or to stop him from exposing a bank fraud. Another theory is the killer may have wanted to cast suspicion on others — presumably a reference to Syria and its allies in Lebanon.

In Lebanon, U.S.-backed Prime Minister Fuad Saniora's Cabinet confirmed its approval of a U.N. plan for a tribunal to try suspects in Hariri's assassination and sent it to Parliament for final approval. But Parliament Speaker Nabih Berri is expected to resist calling a session because he has sided with pro-Syrian government critics who call the Cabinet's action illegitimate because Shiite members resigned.

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The new report was issued amid street protests in Lebanon by pro-Syrian Hezbollah to back its demand for a unity government that could block the tribunal.

In its fourth report to the U.N. Security Council, the International Independent Investigation Commission which Brammertz heads provided new evidence and tantalizing clues about the suicide bombing that killed Hariri and 22 others on Feb. 14, 2005.

Brammertz said his investigators have now identified a number of suspects and witnesses but agreed with Lebanon's prosecutor general that none of their names should be made public to avoid prejudicing any trial.

"The commission has reached a critical stage in its investigations, and with this in mind, the commission and the prosecutor general of Lebanon believe that placing information concerning witnesses and suspects in the public domain would be contrary to the principles of fairness and justice," Brammertz said.

He also revealed that the commission's work on 14 other cases of murder and attempted murder since October 2004 "continues to elicit significant links between each case, and to indicate links to the Rafik Hariri case."

The U.N. team is also helping Lebanese authorities investigate the Nov. 21 assassination of Industry Minister Pierre Gemayel — an event that pushed lingering political tensions in the country to a new crisis point.

A report last year by Brammertz's predecessor implicated Syrian and Lebanese intelligence services and four pro-Syrian Lebanese generals have been under arrest for 15 months accused of involvement in Hariri's murder.

Many in Lebanon blamed Syria for Hariri's death and massive street protests coupled with an international outcry in the wake of the killing forced Syria to end its 29-year domination of its smaller neighbor. Syria has denied involvement in the killing.

The U.N. investigation has determined that a single blast from a Mitsubishi van packed with high explosives was likely detonated by a male suicide bomber who did not grow up in Lebanon but spent his final months there. Brammertz said they were still trying to pinpoint where the bomber came from and were analyzing 33 human parts believed to be the remains of the bomber to that end.

The commission said the most likely scenario was that a bomber triggered the device that killed Hariri from inside or immediately in front of the van.

"The commission has received new information specifying details of the preparation of the van and establishment of the route of the van as it was brought to the St. Georges hotel area prior to the attack," the report said, referring to the hotel next to the bombing site.

The commission is also continuing to investigate "matters arising from a victim at the crime scene who had been discovered in a situation protected from the blast but who was killed by falling masonry," Brammertz said. The report did not identify that victim.

Brammertz said the commission is also investigating Ahmed Abu Adass, a Palestinian living in Beirut who appeared on a video tape claiming responsibility. The investigation "has elicited some useful information" from individuals associated with him in Lebanon and abroad.

The commission has given few details on Adass' identity and a previous report from Brammertz in June said there was no evidence he was involved. But in Tuesday's report, he said investigators were focusing on how Adass was chosen "for the role he played" and his alleged involvement with unnamed individuals in late 2004 and early 2005.

The investigators have discovered that a team of bombers used aliases and six cell phones to communicate on the day of the Hariri bombing and there were indications that they had significant knowledge about security measures.

"The location of the telephones when used, and the purposes for which some of the linking numbers were used have revealed the high degree of security-aware behavior exhibited by individuals under investigation," Brammertz said.

He also said the commission is assuming the Hariri tribunal will be created. But he stressed that his investigation is taking place in a "volatile" and "highly unpredictable" political and security environment that could contribute to the reticence of witnesses.

Brammertz said Syria's cooperation with his investigators "remains timely and efficient" though he criticized 10 other countries — which he did not name — for failing to respond to 22 requests from the commission.

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