TRIPOLI, Oct 23: Libya's transitional leader declared his country's liberation on Sunday after an 8-month civil war and set out plans for the future with an Islamist tone.

The announcement was clouded, however, by international pressure to explain how ousted dictator Muammar Qadhafi had been captured alive days earlier, then ended up dead from a gunshot to his head shortly afterward.

Qadhafi's death in circumstances that are still unclear, and the gruesome spectacle of his body laid out as a trophy in a commercial freezer and on public view, are testing the new Libyan leaders' commitment to the rule of law. Even at the ceremony to declare liberation, two speakers in positions of authority essentially said Qadhafi got what he deserved.

But transitional government leader Mustafa Abdul-Jalil, who made the keynote speech, did not mention the events surrounding Qadhafi's end and called on his people to eschew hatred.

“You should only embrace honesty, patience, and mercy,” Abdul-Jalil told the crowd at the declaration ceremony in the eastern city of Benghazi, the birthplace of the uprising against Qadhafi. He urged Libyans to reconcile their differences.

And he laid out a vision for the post-Qadhafi future with an Islamist tint, saying Islamic Sharia law would be the “basic source” of legislation and existing laws that contradict the teachings of Islam would be nullified. In a gesture that showed his own piety, he urged Libyans not to express their joy by firing guns in the air, but rather to chant “Allahu Akbar,” or God is Great. He then stepped aside from the podium and knelt to offer a brief prayer of thanks.

Using Sharia as the main source of legislation is stipulated in the constitution of neighbouring Egypt. Still, Egyptian laws remain largely secular as Sharia does not cover all aspects of modern day life.

The uprising against Qadhafi erupted in February as part of anti-government revolts spreading across the Middle East. Neighbouring Tunisia, which put the so-called Arab Spring in motion with mass protests nearly a year ago, has taken the biggest step on the path to democracy, voting for a new assembly Sunday in its first truly free elections. Egypt, which has struggled with continued unrest, is next with parliamentary elections slated for November.

Libya's struggle has been the bloodiest so far in the region. Mass protests quickly turned into a civil war that killed thousands and paralyzed the country for the past eight months. Qadhafi's hometown of Sirte was the last loyalist stronghold to fall last week, but Qadhafi's son and one-time heir apparent, Seif al-Islam, apparently escaped with some of his supporters.

Abdul-Jalil paid tribute to the Gulf Cooperation Council, a six-nation alliance led by Saudi Arabia, the Arab League and the European Union. Nato, which aided the anti-Qadhafi fighters with airstrikes, performed its task with “efficiency and professionalism,” he added.

President Barack Obama congratulated Libyans on the declaration.

“After four decades of brutal dictatorship and eight months of deadly conflict, the Libyan people can now celebrate their freedom and the beginning of a new era of promise,” he said.

But just hours before that statement, U.S. Secretary of State Hillary Rodham Clinton and Britain's new defense secretary, Philip Hammond, said a full investigation into Qadhafi's death is necessary.

Hammond said the Libyan revolutionaries' image had been “a little bit stained” by Qadhafi's death, Hammond adding that the new government “will want to get to the bottom of it in a way that rebuilds and cleanses that reputation.”

“It's certainly not the way we do things,” Hammond told BBC television. “We would have liked to see Col. Qadhafi going on trial to answer for his misdeeds.”

An autopsy confirmed that Qadhafi died from a gunshot to the head, Libya's chief pathologist, Dr. Othman al-Zintani, said. However, the pathologist said he would not disclose further details or elaborate on Qadhafi's final moments, saying he would first deliver a full report to the attorney general.

Libya's acting prime minister, Mahmoud Jibril, said he would not oppose an investigation, but cited an official reporting saying a wounded Qadhafi was killed in crossfire following his capture. Addressing the celebrations around Qadhafi's body, Jibril told the BBC in an interview on Sunday: “You have to appreciate the agony that people went through for 42 years.”

The 69-year-old Qadhafi was captured wounded, but alive on Thursday in his hometown of Sirte, the last city to fall to revolutionary forces. Bloody images of Qadhafi being taunted and beaten by his captors have raised questions about whether he was deliberately executed.

Qadhafi's body has been on public display in a commercial freezer in a shopping centre in the port city of Misrata, which suffered from a bloody siege by regime forces that instilled a virulent hatred for the dictator in Misrata's residents.

People have lined up for days to view the body, which was laid out on a mattress on the freezer floor. The bodies of Qadhafi's son Muatassim and his ex-defense minister Abu Bakr Younis also were put on display, and people wearing surgical masks have filed past, snapping photos of the bodies.

The New York-based group Human Rights Watch, which viewed the bodies, said video footage, photos and other information it obtained “indicate that they might have been executed after being detained.”

“Finding out how they died matters,” said Sarah Leah Whitson of Human Rights Watch. “It will set the tone for whether the new Libya will be ruled by law or by summary violence.”

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

The vast majority of Libyans seemed unconcerned about the circumstances of the hated leader's death, but rather was relieved the country's ruler of 42 years was gone, clearing the way for a new beginning.

“If he (Qadhafi) was taken to court, this would create more chaos, and would encourage his supporters,” said Salah Zlitni, 31, who owns a pizza parlor in downtown Tripoli. “Now it's over.”

The long-awaited declaration of liberation starts the clock on Libya's transition to democracy. The transitional leadership has said it would declare a new interim government within a month of liberation and elections for a constitutional assembly within eight months, to be followed by votes for a parliament and president within a year.

At the ceremony in Benghazi, Abdul-Jalil outlined several changes to align with Islamic law.

“This revolution was looked after by God to achieve victory,” he said.

Abdul-Jalil said new banks would be set up to follow the Islamic banking system, which bans charging interest as a practice deemed usury.

For the time being, he said interest would be cancelled from any personal loans already taken out at less than 10,000 Libyan dinars (about $7,500). —AP