Former Libyan leader Moammar Gadhafi is dead.

Libyan provisional government forces killed Gadhafi in a final assault on his coastal hometown of Sirte on Thursday, after launching an uprising in February against his four-decade autocratic rule.

The prime minister of Libya's National Transitional Council, Mahmoud Jibril, confirmed Gadhafi's death at a news conference in Tripoli. He also said it is time for Libyans to build a new, united Libya.

The United States says it received confirmation of the former leader's death from Libyan officials. Gadhafi was 69 years old.

Video footage broadcast on global television networks showed Gadhafi's bloodied corpse lying on the ground, surrounded by NTC forces who later took the body to the western city of Misrata.

The circumstances of Gadhafi's killing were not clear. NTC fighters said Gadhafi was found hiding under ground and was shot and killed as they crushed remaining resistance by his loyalists in Sirte. NATO said its warplanes also attacked two vehicles of pro-Gadhafi forces that were maneuvering around Sirte on Thursday.

Jubilant crowds filled the streets of Tripoli to celebrate Gadhafi's demise. NTC fighters also celebrated the fall of Sirte by firing shots into the air and hoisting Libya's new national flag over what was the last stronghold of Gadhafi loyalists.

Jibril said the NTC will formally announce that Libya has been completely liberated from Gadhafi's rule by Friday.

Provisional government forces had besieged Sirte for weeks, but met with fierce resistance from the loyalists, who were heavily-armed.

Reports from Sirte said NTC fighters also captured one of Gadhafi's sons, Mutassim. But there were conflicting reports about whether he was alive or dead.

Jibril said NTC fighters were pursuing another Gadhafi son, Saif al-Islam, in a village near Sirte.