A U.N. fact-finding team has called for a new international investigation into the killing of former Lebanese Prime Minister Rafik Hariri, after determining that Lebanon's probe into the killing was flawed.

In a report released Thursday, the U.N. team said Lebanese authorities were negligent in carrying out their investigation. The report detailed a host of flaws, including the disappearance of crucial evidence and tampering with the crime scene.

The report did not directly blame Syria for Mr. Hariri's assassination, but said Damascus was behind the political tension and weak security that led to his death. It quoted Hariri aides who said Syrian President Bashar al-Assad threatened Mr. Hariri with physical harm.

Syria denies any involvement in the February 14th explosion that also killed 17 others. Syria's U.N. ambassador dismissed the U.N. report, calling it one-sided.