Libya's interim leader has ordered an investigation into Muammar Gaddafi's death after strong international pressure.
It will aim to determine how he was killed by a bullet to the head shortly after he was captured alive.
Mustafa Abdul-Jalil said that the National Transitional Council has formed a committee to investigate Thursday's killing amid conflicting reports of how Gaddafi died.
Government officials have said initial findings suggest he was killed in the crossfire as his supporters clashed with revolutionary forces seizing control of his hometown of Sirte.
But Mr Abdul-Jalil raised a new possibility, suggesting that Gaddafi could have been killed by his own supporters to prevent him from implicating them in past misdeeds under his regime.
"Let us question who has the interest in the fact that Gaddafi will not be tried. Libyans want to try him for what he did to them, with executions, imprisonment and corruption," he said. "Free Libyans wanted to keep Gaddafi in prison and humiliate him as long as possible. Those who wanted him killed were those who were loyal to him or had played a role under him, his death was in their benefit."
The US, Britain and international rights groups have called for an investigation into whether Libya's former rebels killed a wounded Gaddafi after pulling him out of a drain in Sirte, the last city to fall to revolutionary forces.
Critics also have said the gruesome spectacle of his blood-streaked body laid out as a trophy for a fourth day of public viewing in a commercial freezer raises questions about the new leadership's commitment to the rule of law.
Meanwhile Dozens of bodies, apparently of Gaddafi loyalists, some of whom may have been executed by revolutionary forces, have been discovered in Sirte.
Human Rights Watch said that the discovery of 57 corpses "seems part of a trend of killings, looting and other abuses committed by anti-Gaddafi fighters who consider themselves above the law."
The group urged Libyan authorities to rein in armed groups.