Sirte, Libya: Anti-Gaddafi fighters overran the port of Sirte early on Tuesday, scoring a strategic victory in their battle for control of the defeated Libyan leader's birthplace, his loyalists' most important bastion.

Hundreds of fearful civilians have fled the Mediterranean coastal city in recent days as the new regime's forces have closed in from east, south and west. But as the National Transitional Council troops zero in on the centre of the sprawling city where Gaddafi diehards are believed to be holed up, the threat of destructive urban warfare street-by-street hangs over the remaining residents.

"There were clashes in the night and we now are controlling the port," said Commander Mustafa bin Dardef of the NTC's Zintan Brigade. The port lies on the north side of the city but it is the city centre that Gaddafi's compound and military bunkers lie and NTC fighters said they expected his remaining loyalists to put up fierce resistance.

"As we move closer to the city centre, it's going to be face-to-face street fighting and we are preparing for it," said one fighter, Ali Zaidi.