A LIBYAN father killed his three daughters after pro-Gaddafi soldiers raped them, in an attempt to rid the family of the shame, a human rights group says.

Soldiers raped the sisters aged 15, 17 and 18 , in the town of Tomina, east Libya, US-based Physicians for Human Rights said.

A torn portrait of Libyan leader Moammar Gadhafi. Credit:AFP

When they returned home, their father slit their throats in what the rights group said was most likely an honour killing.

The Gaddafi regime used civilians as human shields and placed children on tanks to deter NATO air strikes, the organisation said. It also found evidence of a pattern of murders, rapes ''disappearances'' and other war crimes during an investigation in the city of Misrata in June.