The Libyan flag. (Creative Commons)

"Four men are in custody and we are interrogating them because they are suspected of helping instigate the events at the US consulate," Sharif told Reuters.

U.S. Ambassador to Libya Christopher Stevens and three other Americans were killed after gunmen attacked the U.S. consulate and a safe house Tuesday night. The attackers were first believed to be part of a mob blaming America for a film they said insulted the Prophet Mohammad, but reports later showed the violence was premeditated.

Libya organized a multiagency task force, combining all available resources to hunt down the suspected Islamic militants, including intelligence, defense and interior officials, according to the Wall Street Journal. Libyan officials declined to say how many suspects they are watching, citing sensitivities of the continuing investigation.

Watch the trailer for the controversial web video "Innocence of Muslims" below:

Read more of Neon Tommy's coverage of Libya here.

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