The sound of heavy fighting was heard on Monday morning near the residence in central Tripoli of embattled Libyan leader Muammar Gaddafi after rebel forces the previous day surged into the capital, taking over many districts.
Fighting was also heard in the south of the capital from around 0400 GMT, with heavy weaponry and automatic rifle fire being deployed, reporter said.
Gaddafi's 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.
The strongman's whereabouts are unknown although he broadcast three audio messages on Sunday as rebel forces were sweeping through the capital and taking over the symbolic Green Square in the heart of the city.
At around 0430 GMT the crackle of Kalashnikov fire could be heard near the Hotel Rixos, which houses most of the foreign media.
In a brief telephonic interview with Al-Jazeera television broadcast on Monday morning, one of Gaddafi's sons, Mohamed, said he was holed up in his house, frightened to leave.
During the broadcast the sound of intense firing could be heard, interrupting the interview. When it resumed, Gaddafi spoke with a tone of panic.
Al-Jazeera gave no indication of where the house is, or even whether it is in Tripoli.