Benghazi: Headquarters of the 'new Libya'
The chief prosecutor of the International Criminal Court has said he will investigate Libyan leader Muammar Gaddafi, his sons and senior aides for crimes against humanity.
Thousands of people are thought to have died after security forces targeted protesters in unrest which began in mid-February.
The BBC's Lyse Doucet reports from Benghazi, where the greatest alleged atrocities took place.
Contributors to this report include Mustafa El Gheriani and Special Forces Officer, Mutaliv Faleh.