The 69-year-old Gadhafi is the first leader to be killed in the Arab Spring wave of popular uprisings that swept the Midde East, demanding the end of autocratic rulers and greater democracy. Gadhafi had been one of the world's most mercurial leaders, dominating Libya with a regime that often seemed run by his whims and bringing international condemnation and isolation on his country for years.
"We have been waiting for this moment for a long time. Moammar Gadhafi has been killed," Prime Minister Mahmoud Jibril told a news conference in the capital Tripoli.
Initial reports from fighters said Gadhafi had been barricaded in with his heavily armed loyalists in the last few buildings they held in his Mediterranean coastal hometown of Sirte, furiously battling with revolutionary fighters closing in on them Thursday. At one point, a convoy tried to flee the area and was blasted by NATO airstrikes, though it was not clear if Gadhafi was in the vehicles. Details of his death remained unverified.
Al-Jazeera TV showed footage of a man resembling the 69-year-old Gadhafi lying dead or severely wounded, bleeding from the head and stripped to the waist as fighters rolled him over on the pavement.
The body was then taken to the nearby city of Misrata, which Gadhafi's forces besieged for months in one of the bloodiest fronts of the civil war. Al-Arabiya TV showed footage of Gadhafi's bloodied body carried on the top of a vehicle surrounded by a large crowd chanting, "The blood of the martyrs will not go in vain."
Celebratory gunfire and cries of "Allahu Akbar" or "God is Great" rang out across the capital Tripoli. Cars honked their horns and people hugged each other. In Sirte, the ecstatic former rebels celebrated the city's fall after weeks of bloody siege by firing endless rounds into the sky, pumping their guns, knives and even a meat cleaver in the air and singing the national anthem.
Libya's new leaders had said they would declare the country's "liberation" after the fall of Sirte.
The death of Gadhafi adds greater solidity to that declaration.
It rules out a scenario that some had feared — that he might flee deeper into Libya's southern deserts and lead a resistance campaign against Libya's rulers. The fate of two of his sons, Seif al-Islam and Muatassim, as well as some top figures of his regime remains unknown, but their ability to rally loyalists would be deeply undermined with Gadhafi's loss.
Information Minister Mahmoud Shammam said he was told that Gadhafi was dead from fighters who said they saw the body.
"Our people in Sirte saw the body," Shammam told The Associated Press. "Revolutionaries say Gadhafi was in a convoy and that they attacked the convoy."
Sirte's fall caps weeks of heavy, street-by-street fighting as revolutionary fighters besieged the city. Despite the fall of Tripoli on Aug. 21, Gadhafi loyalists mounted fierce resistance in several areas, including Sirte, preventing Libya's new leaders from declaring full victory in the eight-month civil war. Earlier this week, revolutionary fighters gained control of one stronghold, Bani Walid.
By Tuesday, fighters said they had squeezed Gadhafi's forces in Sirte into a residential area of about 700 square yards but were still coming under heavy fire from surrounding buildings.
In an illustration of how heavy the fighting has been, it took the anti-Gadhafi fighters two days to capture a single residential building.
Reporters at the scene watched as the final assault began around 8 a.m. Thursday and ended about 90 minutes later. Just before the battle, about five carloads of Gadhafi loyalists tried to flee the enclave down the coastal highway that leads out of the city. But they were met by gunfire from the revolutionaries, who killed at least 20 of them.
Col. Roland Lavoie, spokesman for NATO's operational headquarters in Naples, Italy, said the alliance's aircraft Thursday morning struck two vehicles of pro-Gadhafi forces "which were part of a larger group maneuvering in the vicinity of Sirte."
But NATO officials, speaking on condition of anonymity in accordance to alliance rules, said the alliance also could not independently confirm whether Gadhafi was killed or captured.
The Misrata Military Council, one of the command groups, said its fighters captured Gadhafi.
Another commander, Abdel-Basit Haroun, said Gadhafi was killed when the airstrike hit the fleeing convoy.
One fighter who said he was at the battle told AP Television News that the final fight took place at an opulent compound for visiting dignitaries built by Gadhafi's regime. Adel Busamir said the convoy tried to break out but after being hit it turned back and re-entered the compound. Several hundred fighters assaulted.
"We found him there," Busamir said. "We saw them beating him (Gadhafi) and someone shot him with a 9mm pistol ... then they took him away."
Military spokesman Col. Ahmed Bani in Tripoli told Al-Jazeera TV that a wounded Gadhafi "tried to resist (revolutionary forces) so they took him down."
"I reassure everyone that this story has ended and this book has closed," he said.
After the battle, revolutionaries began searching homes and buildings looking for any hiding Gadhafi fighters. At least 16 were captured, along with cases of ammunition and trucks loaded with weapons. Reporters saw revolutionaries beating captured Gadhafi men in the back of trucks and officers intervening to stop them.
In the central quarter where Thursday's final battle took place, the fighters looking like the same ragtag force that started the uprising eight months ago jumped up and down with joy and flashed V-for-victory signs. Some burned the green Gadhafi flag, then stepped on it with their boots.
They chanted "Allah akbar," or "God is great" in Arabic, while one fighter climbed a traffic light pole to unfurl the revolution's flag, which he first kissed. Discarded military uniforms of Gadhafi's fighters littered the streets. One revolutionary fighter waved a silver trophy in the air while another held up a box of firecrackers, then set them off.
"Our forces control the last neighborhood in Sirte," Hassan Draoua, a member of Libya's interim National Transitional Council, told The Associated Press in Tripoli. "The city has been liberated."