Rebels were advancing towards the Libyan capital after seizing a town between Tripoli and Sirte, the hometown of Libyan leader Moamer Gaddafi, broadcaster Al Jazeera reported on Wednesday.
The commander of the Libyan rebels reportedly said in a statement that "revolutionary forces" had flushed out troops loyal to Gaddafi from the town of al-Heesha, 140 kilometres west of Sirte, DPA reported.
Earlier in the week, the rebels said they had advanced into the centre of the key oil-producing port of Zawiya, 40 kilometres west of Tripoli.
Al-Jazeera reported Wednesday that the rebels had captured the security chief in Zawiya and others loyal to Gaddafi, including senior army officers.
Meanwhile, the United Nations Secretary General's special envoy to Libya, Abdul Ilah al-Khatib, denied holding joint negotiations with officials representing the Gaddafi government and the rebel Transitional National Council in Tunisia.
Al-Khatib said he had separately met officials from both sides and some Libyan citizens, upon their request.
"The Transitional National Council confirms that it has held no direct or indirect negotiations with the Gaddafi regime," added the head of the council, Mustafa Abdul Jalil.
"Gaddafi has to step down and leave Libya or he will be removed by force," Abdul Jalil added in a press conference Tuesday in the rebel stronghold of Benghazi.
The rebels have been fighting for weeks to advance on Tripoli. They have sought to oust Gaddafi since February, and have recently claimed major advances in the strategic oil port of Brega, 750 kilometres east of Tripoli.