Libyan rebels rushed to reinforce the key eastern oil port of Brega today, fearing a new onslaught a day after routing forces loyal to strongman Moamer Kadhafi.

The ragtag opposition army readied anti-aircraft guns and manned checkpoints amid reports of fresh air strikes in the Mediterranean coastal town by Gaddafi's forces, AFP reporters said.

"Gaddafi's forces are preparing another attack for today" so more forces from the nearby town of Ajdabiya have moved to Brega to join the fighting, Mahmoud al-Fakhri told AFP as he manned a checkpoint at the exit of Ajdabiya.

He said he had heard that there had been more air strikes in Brega, but this could not be confirmed independently.

Pro-Gaddafi forces with heavy weaponry attacked Brega at dawn yesterday in their biggest counter offensive yet since the uprising against Gaddafi's 41-year rule erupted on February 15 in eastern Libya.

Despite air strikes throughout the day, the rebels managed to push the regime's forces out of the town, sparking celebrations -- which were themselves targeted by Gaddafi's fighter jets.

On the western edge of Ajdabiya another group were readying an anti-aircraft battery, loading it with ammunition.

"We are ready and we're happy to support," said Driss Abheh AdulWahad as he supervised the loading of shells into the guns.

He said 12 rebels were killed in the fighting yesterday.

Rebel command in the opposition headquarters of Benghazi, Libya's main eastern city, said that between 10 to 15 were killed.

In Ajdabiya, streets were empty early today and there were no visible signs of tension.

Gaddafi warned yesterday that "thousands" would die if the West launched a military intervention in Libya, following calls by some opposition figures for western airstrikes against the regime.

The patchwork Libyan opposition controls swathes of eastern and western Libya including Benghazi and some oil installations. Gaddafi remains firmly in control of the capital Tripoli, where his supporters held a demonstration of support last night.