"The fighters entered the Sirte area but did not reach the city," Al Jazeera's Hoda Abdel Hamid reported from Ajdabiya, as rebels moved onto Gaddafi's hometown from the south and west.

"They pushed from the west to al-Gharbiyat bridge and then retreated to Wadi Jarif, a valley about 36km away from the city centre."

"But there is growing concern about the fate of civilians," our correspondent said, referring to the continuing "crackdown by Gaddafi loyalists on the rest of the population".