By Alexander Dziadosz
AJDABIYAH, Libya (Reuters) - Rebels beat a rapid retreat east on Wednesday, ceding land and a series of oil towns as quickly as they had taken them after Muammar Gaddafi's forces unleashed rockets and artillery on lightly armed rebel forces.
Aided by Western air strikes, rebels had made a two-day charge along more than 200 km (125 mile) of barren coast and seized strategic oil terminals. They have now retreated, giving up gains to Gaddafi's better armed troops.
The failure of the rebels to hold ground and put pressure on Gaddafi, despite more than 10 days of Western-led air strikes, is likely to unsettle the United States, Britain, France and others who want to see the Libyan leader step down.
Hundreds of rebel pick-ups mounted with machine guns and other vehicles streamed east of Brega with little sign of order, heading toward Ajdabiyah, a town that rebels took five days to retake from Gaddafi even after air strikes were launched.
"We are going to Ajdabiyah," said rebel fighter Mohamed al-Abreigi. "We will gather there and, God willing, we will head back to Brega today."
Dozens of rebel vehicles gathered at the western gate to Ajdabiyah, a town which lies about 140 km (90 miles) south of the rebel stronghold of Benghazi. But rebels did not seem to be regrouping into defensive positions there.
One man in military fatigues shouted: "Civilians inside, civilians inside."
When asked what was happening, one rebel said: "We don't know. They say there may be a group (from Gaddafi's forces) coming from the south." To the south is open desert.
Ajdabiyah, battered by the to-and-fro of fighting, stands at the gateway to the rebel held east of Libya. It is located on a key junction with one route heading to Benghazi and another northeast to the oil port of Tobruk near the Egyptian border.
Libyan families were fleeing north to Benghazi as news of the retreat spread. The road out of Ajdabiyah was packed with cars carrying families and their belongings.
Rebels had advanced beyond the coastal town of Bin Jawad, about 525 km (330 miles) east of the capital Tripoli. But as they approached Gaddafi's hometown of Sirte, they came up against the Libyan leader's heavier weaponry.
"Gaddafi's forces have Grad (rockets) which have a range of 40 km (25 miles) ... If we had Grads we could liberate Libya in a day," said rebel fighter Ezzedine Saleh.
Another fighter, Muftah Mohammed, told Reuters: "Kalashnikovs, RPGs (rocket-propelled grenades) and light rockets -- these are our weapons."
Rebels regularly appeal for better weapons from the West and more air strikes. But even some members of the rebel movement have admitted that one of the biggest challenges is keeping discipline in their enthusiastic but inexperienced force.
Few rebel fighters have much formal military training. They have proved keen to race to the front but equally swift to fall back with little sign of order when big guns fire at them. Their own weapons offer little to block Gaddafi's advance.
"Where is the French air force? We won't be able to get to Sirte except with help from the French air force," said rebel Rafa Abbas near Ras Lanuf, moments before aircraft roared overhead. A series of loud booms followed.
A rebel fighter, Ahmed, returning from Ras Lanuf, told Reuters: "The French planes came and bombed Gaddafi's forces."
But the apparent aerial attack showed no sign of slowing down Gaddafi's advance or halting the pace of the rebel retreat.
Some 10-15 km (6-10 miles) west of Brega, around a dozen rebel fighters stopped by the road and trained their guns south into the Sahara. Wisps of smoke could be seen in the distance.
"They (Gaddafi's forces) are coming from the desert," yelled one fighter. Another fired his Kalashnikov rifle in the air to scare away a group of camels.
There was no sign of the rebels forming any determined defense of the sprawling oil town of Brega.
(Writing by Edmund Blair and Ibon Villelabeitia in Cairo)