The chief prosecutor for the International Criminal Court says there are "serious suspicions" that the death of Libyan leader Muammar Qaddafi was a war crime.

Luis Moreno Ocampo told reporters after briefing the U.N. Security Council on Thursday that he sent a letter to the head of the National Transitional Council asking about the government's plans to investigate alleged war crimes by all parties, including the rebels.

The uprising against Qaddafi's 42-year rule ended in October with Qaddafi's capture and death in unclear circumstances. Witness accounts and video of the deposed dictator after his capture by rebel fighters show that he was beaten and abused by his captors, and there were strong indications he was killed in custody.