An autopsy performed on the body of Col. Moammar Gadhafi has confirmed that the former Libyan dictator was killed by a shot to the head. The autopsy was performed by Libya's chief forensic pathologist, Dr. Othman el-Zentani.

Amnesty International, which has called for a full, independent and impartial investigation into his death, including pressing war crimes charges against the guilty parties if Gadhafi was executed, has also charged the rebels with mistreatment of detainees, including torture and lynching of captured pro-Gadhafi fighters. Both U.S. Secretary of State Hillary Clinton and UK Defense Secretary Philip Hammond have also called for a full investigation.

There is international unease about increasingly graphic and disturbing images of the abuse of a body that appears to be Gadhafi's, following his capture and the fall of his hometown of Sirte on Thursday. 

Syrian-based Al-Rai TV station, which has served as a mouthpiece for the Gadhafi clan, said the dictator's widow, Safiya, also demanded an investigation.

I am proud of the bravery of my husband, Moammar Gadhafi, the holy warrior, and my sons who confronted the aggression of 40 countries over the past six months, the station quoted her as saying.

Meanwhile, 53 bodies discovered over the weekend were those of loyalists of the former Libyan leader, Human Rights Watch said. The group said fighters from Misrata were in control of the Hotel Mahari in Sirte, where the badly decomposed corpses were found.

This latest massacre seems part of a trend of killings, looting and other abuses committed by armed anti-Gadhafi fighters who consider themselves above the law, said Peter Bouckaert, the Human Rights Watch researcher who investigated the killings.

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