On October 6, an NTC military commander Col Abdel Salam Gadallah said three quarters of the city was in their hands.

Hundreds of vehicles have advanced on the city from both the east and the west and are close to the centre. Thousands of civilians have already left Sirte but many more are thought to have remained behind.

Sustained tank and mortar fire has been targeting Sirte and there are huge columns of smoke across the city, some 360km (225 miles) east of Tripoli, with many buildings struck and on fire.

This appears to be the final push for Col Gaddafi's home town as the country has been unable to think about the future until Sirte falls.

The interim authority's troops are coming from both Misrata in the west and Benghazi in the east.

The NTC troops have given civilians in Sirte the opportunity to leave, but there are fears that thousands have been unable to do so or believed warnings by pro-Gaddafi fighters that they would be attacked by the interim forces if they surrendered.