Libyan officials showed journalists the bodies of five people who government spokesman Mussa Ibrahim said died in a NATO air strike on a residential area of the capital Tripoli early on Sunday.
Reporters were first taken to the Al-Arada neighbourhood where rescue teams helped by bystanders were desperately looking for survivors among the wreckage of a two-storey block of flats.
An AFP correspondent saw two bodies pulled from the rubble.
Journalists were then taken to a Tripoli hospital where they were shown the bodies of a woman and two toddlers that officials said were members of the same family and had died in the same raid.
Ibrahim said he feared the death toll would rise as the building was home to at least 15 people. He accused NATO of "deliberately targeting civilians" in an "act of barbarism."