Alastair Leithead says anti-Gaddafi fighters have made a "major breakthrough".
Libya's interim government forces are renewing their attack on Sirte, one of the last pro-Gaddafi strongholds.
National Transitional Council (NTC) fighters have surrounded the city and Nato warplanes are reported to be blasting targets inside.
It comes a day after NTC troops launched a surprise assault which took them, at one stage, to within 1km (0.5 miles) of the city centre.
Sirte is the birthplace of ousted Libyan leader Col Muammar Gaddafi .
It is not known if Col Gaddafi or members of his family are in the city.
The city has always been a hugely symbolic target for the NTC, and it seems close to being won, reports the BBC's Alastair Leithead, who is with anti-Gaddafi forces in Sirte.
Meanwhile, pro-Gaddafi forces have killed at least five NTC soldiers in an attack on the southern town of Ghadames, on the border with Algeria, officials and witnesses say.
Military spokesman Ahmed Bani told a news conference they had information the attackers were related to Col Gaddafi's son Khamis.
Gaddafi snipers
Troops were reported to be setting up new roadblocks and checkpoint, posting snipers at various key points and cleaning their guns in preparation for a final assault on Sirte.
One fighter on the east of the city told the AFP news agency that they had been told by their commanders to keep their guns ready.
"We expect fierce urban battle once we fully enter Sirte," Maatiz Saad said.
Fighter Ahmed Mohammed Tajuri in the west of the city told AFP they had been ordered to leave downtown Sirte on Saturday evening "because Nato has a mission to do there", without giving more details.
Nato air strikes have played a major role in the conflict as part of the alliance's UN-mandated mission to protect civilians.
Our correspondent says that the troops he is with - some 30km east of the centre of Sirte - are making big advances towards the city, meeting little resistance so far from pro-Gaddafi force.
He says he has seen a number of civilians fleeing from Sirte who appear to be unaware that Tripoli fell more than a month ago.
NTC fighters tried to push into Sirte last weekend but were driven back by pro-Gaddafi forces entrenched in the city.
Source: bbc
| Disclaimer: Opinions expressed here are those of the writers and do not reflect those of Peacefmonline.com. Peacefmonline.com accepts no responsibility legal or otherwise for their accuracy of content. Please report any inappropriate content to us, and we will evaluate it as a matter of priority. |
