ICC chief prosecutor Luis Moreno-Ocampo told the UN Security Council on Wednesday that he will seek three arrest warrants for crimes against humanity in Libya.
Moreno-Ocampo said the murder and persecution of civilians was still being carried out by Muammar Gaddafi's regime and that more cases would follow.
He told the 15-nation council that "thousands" have died in Libya since the start of the uprising on February 15. The ICC is also investigating the deaths of dozens of sub-Saharan Africans in the rebel capital of Benghazi by an "angry mob" who believed they were Kadhafi mercenaries.
Diplomats have said Gaddafi is likely to be on the first list of warrants, but Moreno-Ocampo did not name the initial targets.
He did say though that the Libyan government started preparing to counter protests weeks before they started -- warned by uprisings in Egypt and Tunisia.
"As early as January, mercenaries were being hired and brought into Libya," he told the council.
He said he would seek warrants in coming weeks saying he had witness accounts, videos and picture evidence to back his case.
"I will request the judges to issue arrest warrants against three individuals who appear to bear the greatest criminal responsibility for crimes against humanity" committed in Libya since February 15, he said. Moreno-Ocampo said that any arrests would need "serious planning and preparation" which he said the Security Council has to start now.
"Widespread and systematic attacks against the civilian population have been and continue to be committed in Libya, including murder and persecution as crimes against humanity," Moreno-Ocampo said.