Ousted Libyan dictator Moammar Gadhafi was shown no mercy and brutally killed by the same people he ruled over for more than 40 years. Graphic pictures and videos captured his final moments. NBC's Richard Engel reports.
The slaying of former Libyan leader Moammar Gadhafi, who was captured and killed by rebels in October, may have been a war crime, the chief prosecutor of the International Criminal Court said late Thursday.
"I think the way in which Mr Gadhafi was killed creates suspicions of ... war crimes," ICC prosecutor Luis Moreno-Ocampo told reporters.
"I think that's a very important issue," he said. "We are raising this concern to the national authorities and they are preparing a plan to have a comprehensive strategy to investigate all these crimes."
Under pressure from Western allies, Libya's National Transitional Council has promised to investigate how Gadhafi and his son Muatassim were killed.
Cell phone footage showed both alive after their capture. The former Libyan leader was seen being mocked, beaten and abused before he died. NTC officials said crossfire was to blame for his death.
A lawyer for Gadhafi's daughter said on Wednesday he had written to the ICC to ask if an investigation had been launched into the killing of her father and brother.
Patrick Baz / AFP - Getty Images, file
A defaced portrait of Libyan leader Moammar Gadhafi is pictured in Tripoli on September 1.
A copy of the letter, seen by Reuters, said that Mommar Gadhafi and Muatassim were "murdered in the most horrific fashion with their bodies thereafter displayed and grotesquely abused in complete defiance of Islamic law."
Story: Gadhafi daughter seeks ICC probe into his killing
The U.N. Security Council referred Gadhafi's crackdown on pro-democracy demonstrators to the ICC in February and authorized military intervention to protect civilians in March. The ICC indicted Gaddafi, his son Saif al-Islam and the former intelligence chief for war crimes.
Saif al-Islam is now in the custody of the Libyan authorities who have said they plan to try in him in Libya instead of handing him over to The Hague-based ICC. Moreno-Ocampo has said this was possible.
Story: Libya can try Gadhafi's son, Seif
Moreno-Ocampo has also said he was investigating allegations that the anti-Gadhafi forces and NATO were also guilty of war crimes during the civil war.
Meanwhile, Libya's new interim government, which has been in control of the oil-producing OPEC member since Gadhafi fled Tripoli in August, estimates that more than 40,000 Libyans were killed during the country's civil war.
"Gadhafi was responsible for these deaths," Libyan U.N. envoy Ibrahim Dabbashi told Reuters on Thursday.
Sen. John McCain, R-Ariz., tells TODAY's Savannah Guthrie says it would have been better if former Libyan dictator Moammar Gadhafi, who was brutally murdered Thursday by the people he ruled over for more than 40 years, had been hauled off to an international criminal court to be held accountable for his crimes.
His comments came in response to calls by New York-based campaigners for NATO to investigate its role in the deaths of civilians during the civil war.
Fred Abrahams of Human Rights Watch (HRW), a rights advocacy group, is in Libya and has been investigating several dozen civilian casualties allegedly caused by NATO.
Abrahams has been investigating the matter to determine as precisely as possible how many civilians were killed by the NATO airstrikes, which began in March and ceased in October.
"By our count, up to 50 civilians died in the (NATO) campaign, perhaps more," Abrahams told Reuters.
"We're not alleging unlawful attacks, let alone war crimes," he said. "We believe the onus is on NATO to investigate these cases thoroughly so they can identify and correct the mistakes."
He urged NATO to consider compensation "as appropriate."
However, Libya's government has not asked NATO to investigate.
"There is no need for a NATO investigation," Dabbashi said. "Usually it is acceptable that there will be some civilian casualties because of some errors."
A press officer at NATO said the alliance was unaware of any reports from rights groups but was ready to receive them.
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The Associated Press and Reuters contributed to this report.