A U.N. inquiry into the assassination of former Lebanese Prime Minister Rafik Hariri is probing possible links to other politically motivated killings. The Security Council is set to extend and upgrade the inquiry.

Belgian prosecutor Serge Brammertz told the Security Council the Hariri murder investigation is examining what he called "obvious links" to 14 similar attacks in Lebanon since late 2004.

But he said the inquiry is stymied by the inability of Lebanese authorities to gather key evidence. "All 14 cases are at present lacking significant forward momentum. The reasons for this include the lack of Lebanese forensic capacity to collect and analyze evidence effectively, and a lack of horizontal coordination among the cases due to an apparent fragmentation within the Lebanese judicial and law enforcement system," he said.

Hariri, a vocal critic of Syrian domination of Lebanon, was killed in a bomb blast in Beirut in February 2005. Other attacks about the same time targeted prominent Lebanese journalists and others who had spoken out against Syria's control of Lebanon's political and security institutions.

Syria has denied involvement in the killings, and condemned the Hariri assassination as a "heinous crime." Syria's deputy foreign minister, Fayssal Mekdad, Wednesday accused what he called "certain parties" of providing false evidence in an attempt to pressure his country. "Many of the witnesses were bribed, were coerced, were pushed to make statements. These were uncovered. One of the witnesses in Paris, one of them in Damascus, who fled away from Lebanon, and many others whom we are not aware of," he said.

Brammertz's predecessor, German prosecutor Detlev Mehlis, had charged Syria with obstructing the assassination inquiry. Brammertz declines to repeat that charge in his new report. Instead he describes cooperation from Damascus as "generally satisfactory."

But Washington's U.N. ambassador, John Bolton, says Brammertz's words should be interpreted to mean Syria has not cooperated completely. "It's very clear that Brammertz does not say in the report that Syria has fully cooperated. He says, during this reporting period, their cooperation has been generally satisfactory. Maybe in a pass/fail system, that says 'pass' for this reporting period, But that's hardly a ringing endorsement," he said.

The earlier Mehlis report also suggested the involvement of senior Syrian intelligence officials and their Lebanese allies in the Hariri killing. Brammertz shied away from that conclusion, but told journalists the assassination was clearly planned and executed by a powerful force, not by individuals. "We don't think that individuals are able from an operational and organizational perspective, or even from a tactical perspective, to organize and to perpetrate a crime of this magnitude. So we are of course convinced that strong structures must be behind to conduct this investigation," Brammertz said.

Brammertz asked the Security Council Wednesday to give him another year to finish his investigation so that, in his words, "justice will eventually be done."

The United States earlier circulated a resolution that would grant the extension and provide Lebanese authorities with more help in probing other similar killings.