By Stephanie Nebehay
GENEVA (Reuters) - The United Nations and human rights groups called on Friday for a full investigation into the death of Libyan leader Muammar Gaddafi and voiced concerns that he may have been executed, a war crime under international law.
Images filmed on mobile phones before and after Gaddafi's death showed him wounded and bloodied but clearly alive after his capture in his hometown of Sirte on Thursday, and then dead amidst a jostling crowd of anti-Gaddafi fighters.
"If you take these two videos together, they are rather disturbing because you see someone who has been captured alive and then you see the same person dead," U.N. human rights spokesman Rupert Colville told Reuters Television.
Asked whether Gaddafi may have been executed, he said: "It has to be one possibility when you look at these two videos. So that's something that an investigation needs to look into."
Under the Geneva Conventions which lay down the rules of conduct in armed conflict, it is prohibited to torture, humiliate or murder detainees.
The International Committee of the Red Cross (ICRC), which upholds respect for the 1949 pacts, said it had no information on Gaddafi's death. "In general, a captured person must be treated correctly," an ICRC spokesman said.
Russia believes that Gaddafi should have been treated as a prisoner of war according to the Geneva Conventions and should not have been killed, Foreign Minister Sergei Lavrov said on Friday, calling for an investigation.
"If Colonel Gaddafi was killed after his capture, it would constitute a war crime and those responsible should be brought to justice," Claudio Cordone, senior director at Amnesty International, said in a statement.
Peter Bouckaert of Human Rights Watch, interviewed by CNN in Sirte near the drainage ditch where Gaddafi was captured, said: "We do not think he was caught in crossfire. Did Muammar Gaddafi die from wounds or did he receive a fatal head wound after he left this area?
"We are calling for an autopsy and an investigation. This is a blemish on the new Libya that he died under suspicious circumstances," he said.
Some 95 bodies were found after Libyan transitional forces took Gaddafi's besieged hometown, including several bodies executed with gunshots to the head, according to Bouckaert.
Gaddafi's body lay in an old meat store on Friday as arguments swirled over his burial and the circumstances of his death.
With a bullet wound visible through the familiar curly hair, the corpse shown to Reuters in Misrata bore other marks of the violent end to a violent life that was being broadcast to the world in snatches of grainy, gory cellphone video.
A television station based in Syria that supported Gaddafi said on Friday that the slain Libyan leader's wife had asked for a U.N. investigation into his death.
ARRESTED ALIVE, KILLED LATER
Colville said it was a fundamental principle of international law that people accused of serious crimes should be tried if possible. The International Criminal Court (ICC) issued arrest warrants in June for Gaddafi, his son Saif al-Islam and their intelligence chief for crimes against humanity.
"Summary executions are strictly illegal under any circumstances. It's different if someone is killed in combat. There was a civil war taking place in Libya. So if the person died as part of combat, that is a different issue and that is normally acceptable under the circumstances," he told Reuters.
"But if something else has happened, if someone is captured and then deliberately killed, then that is a very serious matter," he said.
Libya's interim Prime Minister Mahmoud Jibril said Gaddafi was killed in a "crossfire" while being brought to hospital after his capture. A doctor who examined Gaddafi's body said he had been fatally wounded by a bullet in his intestines.
But a senior interim ruling National Transitional Council source told Reuters Gaddafi was killed by his captors: "While he was being taken away, they beat him and then they killed him," the source said. "He might have been resisting."
(Reporting by Stephanie Nebehay; additional reporting by Rania El Gamal in Misrata and Gleb Bryanski in Moscow; Editing by Myra MacDonald)