Street fighting has raged in Sirte for a second day as troops loyal to Libya's transitional government confront the remnants of ex-leader Col Muammar Gaddafi's forces.

利比亚过渡政府军在苏尔特城遭遇前领导卡扎菲的残余部队，混战已持续两天。

Interim¹ authority forces seized control of a key boulevard（大马路） , isolating² a conference centre where Gaddafi loyalists have been holed up.

Thousands of civilians³ remain trapped.

Once Sirte falls, Libya's leaders say they will declare liberation, even if Col Gaddafi remains⁴ on the run.

"There is a very vicious（恶毒的） battle now in Sirte," said National Transitional Council (NTC) chairman Mustafa Abdel Jalil in the capital Tripoli.

"Today our fighters are dealing⁵ with the snipers that are taking positions and hiding in the city of Sirte."

Snipers on rooftops

On Friday, NTC forces launched what they called a final assault on Sirte, pushing pro-Gaddafi fighters back from their positions and towards the city centre.

But on Saturday, their rapid advance slowed down as they fought street by street to take control of the city, Col Gaddafi's birthplace and a symbolic⁶ second capital for Libya.

Pro-Gaddafi snipers fired from the rooftops of the Ouagadougou conference centre, the university and a complex of flats.

However, the NTC side won control of a key boulevard which connects the Ouagadougou centre to central Sirte.

NTC fighter Faraj Leshersh told Reuters the Gaddafi loyalists were experts at operating unseen, using trenches⁷ or burning tyres to give themselves cover to move between buildings.

"They took advantage of the dust and they advanced a little," he said. "There is 500m [yards] between us and them."

Civilians continued to leave Sirte on foot and by car. They were stopped and searched by NTC forces at checkpoints.

The NTC gave civilians the opportunity to leave before the assault began.

However, thousands remained in the city, unable to get out or fearful after warnings from pro-Gaddafi fighters that they would be attacked by the interim forces if they surrendered.

Efforts to negotiate with loyalist commanders have also failed. On Thursday, Col Gaddafi delivered an audio message urging Libyans to take to the streets "in their millions" to resist the interim leaders.

Pro-Gaddafi forces also control the desert enclave（被包围的领土） of Bani Walid, but it is seen as less significant as it does not lead to any exit routes from the country.