A broadcast report apparently based on extensive leaks from within the United Nations-backed tribunal probing the 2005 assassination of former Lebanese Prime Minister Rafik Hariri, connects the Shiite militia Hezbollah and one of the former premier's top deputies to the killing.
The investigation by the Canadian Broadcasting Corp., which was widely cited in news reports Monday throughout Lebanon, complicates efforts to resolve a standoff that threatens the nation's security.
But the lengthy report also tarnishes the work of the Special Tribunal for Lebanon, suggesting it repeatedly dismissed the findings of its own investigators and suppressed suspicions out of political considerations, potentially emboldening Hezbollah in its effort to force the government to disavow the tribunal's work.
Tensions over the anticipated indictment of Hezbollah members in the killing of Hariri, the longtime leader of the country's Sunni community, have threatened Lebanon's fragile peace. Hezbollah has warned that it would not hand over any member and threatened to "cut off the hand" of any entity that tried to make an arrest.
"Hezbollah has come to the conclusion that anything short of vindication of all accusations will not be acceptable," said Kamel Wazne, founder of the Center of American Strategic Studies in Beirut, a think tank that covers regional issues.
The Obama administration, like that of President George W. Bush, has pushed hard for indictments by the tribunal, which it strongly supports.
Regional powers have embarked on a flurry of diplomatic meetings in an effort to stave off an escalation of already-high tensions.
Over the summer, a minor argument over a parking spot between a Hezbollah official and Sunnis spiraled within 48 hours into a deadly night of sectarian violence. Lebanese fear a version of the May 2008 conflict between Shiites and Sunnis, triggered by the government's effort to rein in Hezbollah, which nearly plunged the country into civil war.
Diplomatic efforts are centered on an initiative by Saudi Arabia, the Hariri family's patron, and Syria, which backs Hezbollah. But the illness of Saudi King Abdullah, 86, who has traveled to the United States for treatment of a herniated disc, is complicating the effort.
"There seems to be a vacuum on who is calling the shots in Saudi," Wazne said.
The premier of Qatar, which brokered a 2008 deal between Lebanon's Shiite and Sunni-led alliances, was in Beirut on Monday; Lebanese President Michel Suleiman headed to Qatar for a two-day visit.
Prime Minister Recep Tayyip Erdogan of Turkey, which has emerged as a major power broker in the Middle East, is scheduled to arrive in Beirut on Wednesday. Meanwhile, Lebanese Prime Minister Saad Hariri, son of the slain former leader, is scheduled to travel Saturday to Iran, Hezbollah's strategic ally, a source in his office said.
"It's impressive how much diplomacy there is, and how intense is the action diplomatically," said Rami Khouri, a scholar at American University of Beirut and a frequent commentator. "Nobody wants to see this place explode."
Analysts say the diplomacy is meant to persuade Iran and Syria to rein in Hezbollah, which has heightened its rhetoric against the tribunal since word leaked that indictments were likely by early next year. Iran will probably try to convince Hariri to disavow the tribunal.
The CBC report described how investigators used cellphone records to identify those suspected of conspiring to assassinate Rafik Hariri, who was killed by a bomb that exploded as his car passed by on a Beirut street. The network identified individuals, including top Hezbollah officials.
But more than once, reports detailing calling patterns that pointed to a group of alleged assassins and their accomplices were lost or ignored by higher-ups, CBC said. The leaders of the Special Tribunal for Lebanon, including chief prosecutor Daniel Bellemare, a Canadian, are described as timid and vain.
The CBC report said investigators suspected that Lebanese Internal Security Forces intelligence chief Wissam Hassan, an ostensible ally of the Hariri family, had a role in the plot and in subsequent efforts to squelch incriminating investigative routes.
"He would have been ideally placed to provide information about all aspects of Hariri, from insight into his political maneuverings to his travel and security arrangements," said a confidential U.N. memorandum about Hassan obtained by the CBC. "His alibi is weak and inconsistent, and does not appear to have been independently verified."