Heavy fighting raged Monday near the Tripoli compound of embattled Libyan leader Muammar Gaddafi, an AFP reporter said, a day after jubilant rebel forces surged into the symbolic heart of the capital.
Fighting was also heard from around 0400 GMT in the south of the capital, where there were exchanges of heavy weaponry and automatic rifle fire.
Rebel leaders had earlier warned that pockets of resistance remained despite most of Gaddafi's defenders vanishing during the rebels' lightning charge through Tripoli on Sunday.
The whereabouts of the Libyan strongman were unknown Monday but one of his sons, Seif al-Islam had been arrested while another, Mohamed Gaddafi was interviewed by Al-Jazeera television cowering in his house, afraid to leave.
Gaddafi broadcast three defiant audio messages on Sunday, vowing he would not surrender and urging the people of Tripoli to "purge the capital, even as rebel forces swept through the capital and took over the symbolic Green Square at the waterfront. But he has not been seen in public for weeks.
A diplomatic source said the strongman could still be in his Bab al-Aziziya compound in central Tripoli.
"He is still in Tripoli and could be in his residence at Bab al-Aziziya," said the source, who met the embattled strongman within the past two weeks.
The Bab al-Aziziya compound has been blasted regularly since the start of the international military intervention in Libya on March 19 and most of the buildings in the complex have been flattened.
But Gaddafi has many bunkers there that he could take cover in, the diplomatic source said.
In a brief telephonic interview with Al-Jazeera television broadcast Monday morning, Mohamed Gaddafi admitted the regime had made mistakes.
"I was not part of the security or official systems of the government to know what was going on. I think that the lack of reason and wide vision led Libya to where it is now," he said in the interview.
"Our problems were simple. They could have been solved," he said as the crackle of gunfire, which he said was "inside" his home, interrupted his conversation.