Pro-government militias have clashed with fighters in a former stronghold of the late dictator Muammar Gaddafi for the third consecutive day, the spokesman for the Libyan military's chief of staff said, after talks to end the stand-off broke down.
Violence has flared periodically over the last year in Bani Walid, the most significant town in Libya still resisting the country's new authorities since the end of the country's civil war last year.
Fighters of the pro-government Libya Shield militia have besieged the town, some 90 miles south east of Tripoli, for the past several weeks, blaming residents for the death of a well-known anti-Gaddafi rebel.
On Wednesday, they attacked the town with mortar and artillery, then launched a ground assault after saying that negotiations to hand over the suspects in the killing had failed.
A day later, Libya's Defence Ministry deployed military forces to the town, although officials say they have not taken part in the fighting that has killed at least seven people and wounded 80 so far.
Libya's interim president, Mohammed el-Megarif, expressed regret for the bloodshed but voiced his support for the government-led offensive in a televised speech. "This is not targeting a region, a tribe, or unarmed civilians but outlawed men. This is to impose state legitimacy," he said.
The spokesman for the chief of staff, General Ali al-Shekhli, said town elders and tribal leaders have promised to hand over the men accused of killings during and after Libya's civil war to the national army instead of militia forces that have besieged the town for weeks.
The fighting comes on the eve of the anniversary of Gaddafi's capture and killing last year, which brought an end to an eight-month civil war that killed thousands.
Since the conflict's end, Bani Walid has changed hands twice. Rebels captured it last October at the end of the war, but fighters loyal to Gaddafi shortly afterwards rose up and expelled them, along with pro-revolution residents.
There was an uneasy stand-off that ended when Omran Shaaban, a rebel hailed as the fighter who caught Gaddafi, was reportedly kidnapped, tortured and killed by Bani Walid residents. Pro-government militias deployed to the outskirts of Bani Walid then imposed a siege and threatened to take it over by force.