| NTC military commanders said they encountered heavy resistance from Gaddafi loyalists in Bani Walid [Al Jazeera]
Libyan interim government forces say they have entered Bani Walid, one of the last outposts still loyal to deposed leader Muammar Gaddafi, with National Transitional Council fighters saying they now control about 60 per cent of the town.
NTC military commanders said they encountered heavy resistance from Gaddafi loyalists in the town, located about 170km southeast of Tripoli, on Sunday.
Meanwhile, fighting has eased in the city of Sirte, Gaddafi's birthplace and his final coastal stronghold.
Jamal Salem, a commander of the NTC forces, said: "We attacked [Bani Walid] this morning from the southwest. Our men were inside the town this afternoon. But there was heavy resistance" from the Gaddafi loyalists.
The NTC forces mounted their fresh assault on the stronghold after launching a barrage of artillery fire against the positions of pro-Gaddafi fighters.
Abdallah Kenshil, an NTC official, told local television channel Libya Al-Ahrar that the fighters had reached the town centre, but the claim could not be independently verified.
A commander from the city of Az Zawiyah said three of his men were killed in the fighting.
Bani Walid is surrounded by NTC fighters, but their commanders pulled them back last week after suffering heavy losses, and to prepare for a new offensive against the 1,500 pro-Gaddafi fighters thought to remain there.
Meanwhile in Sirte, on the Mediterranean coast, where fierce clashes between NTC forces and those loyal to deposed leader Gaddafi have raged for a month, Sunday saw a lull with only intermittent shelling and rocket-fire, AFP
"We are shelling with tanks and anti-aircraft weapons and then we will send our troops onto the streets," said Salem Ahmed, a tank commander from the eastern city of Benghazi.
Ahmed said the advance was being held up by pro-Gaddafi snipers: "A few snipers can stop an army.
"They are very professional. They shoot in the heart, the head, the chest."
The focus of the NTC operations are two seaside residential neighbourhoods, the Dollar and Number Two, where Gaddafi loyalists are holed up.
One NTC fighter told AFP there had been an exodus of civilians from the two areas on Sunday and that the besieging troops wanted to give others the chance to leave.
Sunday's lull contrasted sharply with the previous day when Gaddafi loyalists mounted a fierce counter-attack in Sirte, forcing back the NTC fighters under a barrage of rockets and shelling.
A medic at a field hospital behind the eastern front line said four NTC fighters were killed and 22 wounded in the fighting on that side of the city on Saturday.
"Those killed were mainly from sniper bullets. And the wounded were injured by explosions and rocket attacks," Ahmed Bushariya told AFP.
Khamis death 'unconfirmed'
In another development, a US official, speaking on condition of anonymity, told the Reuters news agency that Washington could not yet independently confirm reports that the deposed Libyan leader's son Khamis had died in fighting southeast of the capital Tripoli on August 29.
On Monday, a television station based in Syria that supports Gaddafi confirmed Khamis' death, along with that of his cousin Mohammed Abdullah al-Senousi, Gaddafi's intelligence chief, saying they were killed during a battle with NTC forces in the city of Tarhouna, 90km southeast of Tripoli.
The Arrai TV station said Khamis and Senousi died "while confronting the enemies of their homeland" on August 29.
The US official said similar information was being received in Washington from "reliable sources".
NTC military officials had said in August that Khamis was killed in Tarhouna and buried in the city of Bani Walid but
there was no confirmation at the time from Gaddafi loyalists.
Khamis had been reported dead twice during the uprising, only to reappear.