Libyan rebels have taken over Col Muammar Gaddafi's compound in Tripoli, one of the final areas under the Libyan leader's control.
TV footage showed fighters destroying statues and firing guns into the air in celebration inside the compound.
Rebel commanders targeted the buildings as they have served as a symbol of Col Gaddafi's rule.
It is not known if the colonel or any members of his family are in the Bab al-Aziziya compound.
Heavily armed fighters had streamed into the capital on Tuesday morning in dozens of pick-up trucks to take part in the attack.
Hours later, they breached a wall and quickly overran the compound.
The rebels were shown destroying statues of Col Gaddafi and firing guns in the air.
There were no obvious signs of resistance, despite reports that hundreds of Gaddafi loyalists had been tasked with guarding the compound.
The Bab al-Aziziya complex is reported to be connected by underground tunnels to various key locations across the city.
It houses military buildings, Col Gaddafi's main residence, a library and government offices.
The whereabouts of Col Gaddafi and his family are not clear.
The BBC's Rana Jawad in Tripoli says there is a real sense that this is the end of Col Gaddafi's rule, but the real celebrations will not begin until he and his family are found.
Next moves
Early on Tuesday the colonel's son Saif al-Islam spoke to journalists at the Rixos Hotel, hours after the rebels said he had been captured.
He insisted the government had "broken the backbone" of the rebel offensive and that his father's supporters were winning the battle.
But Western politicians, rebel leaders and the Nato military alliance dismissed his claims.
"A brief appearance at the dead of night doesn't indicate to me somebody who is in control of a country, or capital, or of anything much at all really," said Nato spokeswoman Oana Lungescu.
A rebel leader said that his reappearance was unhelpful.
"He was captured and apparently he escaped; that's the information we're getting. To be honest, it's an embarrassment," Hany Hassan Soufrakis told the BBC.
Meanwhile, members of the rebel National Transitional Council (NTC) in Benghazi said they planned to fly to the capital on Wednesday to start work on forming a new government.
NTC chairman Mustafa Abdul Jalil also said all Gaddafi aides would face justice and fair criminal trials.
"I will stand trial for years I served as a minister in the Gaddafi government," he told a news conference in Benghazi.
He advised Libyans to be tolerant, saying they should "avoid taking matters into their own hands and... abide by court rulings".
The NTC leadership has expressed concern about revenge attacks by some of the mosaic of different groups which make up the revolutionary army.
In other developments:
Turkey has announced it is giving $300m (£181m) to the NTC, including funds to form the new government
Nato says it has destroyed two rocket launchers that were aiming fire at the town of Brega
The International Organization for Migration (IOM) said a boat it sent to Tripoli to evacuate migrant workers was unable to dock because of the security situation
Egypt and Bahrain formally recognised the NTC as the legitimate government of the Libyan people
The rebels swept into Tripoli at the weekend, but after a swift advance, they met stiff resistance in a number of areas on Monday.
World leaders have urged Col Gaddafi to step down. US President Barack Obama said elements of the Gaddafi regime continued to pose a threat.
The uprising against Col Gaddafi's 41-year rule began in February. The rebels held the east of the country and pockets of the west, before making their push towards the capital at the weekend.
Nato air strikes have been targeting Col Gaddafi's forces, acting on a UN mandate to protect civilians.
