Ajdabiya, LIBYA - Rebel fighters in eastern Libya fought off an attack by government troops in the town of Ajdabiya on Sunday, a day after retreating from a key oil facility around 100 kilometres farther west.

Forces loyal to longtime leader Muammar Gaddafi advanced on Ajdabiya under a heavy artillery barrage in the morning and fought at close range with rebels on the town’s southern outskirts before a counterattack forced them back, witnesses said.

On Saturday, with the help of NATO air strikes along the main coastal road, rebels reached the outskirts of Brega, the site of a major oil and petrochemical port west of Ajdabiya.

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But a sandstorm that began overnight hampered air cover, and by Sunday morning rebels had retreated.

Dozens of civilian vehicles, many of them carrying families, fled Ajdabiya throughout the morning, and some rebels also appeared to join the withdrawal.

Two fighters were injured in the battle, suffering superficial shrapnel wounds during the bombardment, but none were seriously injured or killed, doctors at Ajdabiya Hospital said.

In response to the advance by Gaddafi’s forces, the opposition Transitional National Council issued orders that casualties should no longer go to Ajdabiya Hospital and should instead be sent directly to Benghazi, the seat of the rebel government around 160 kilometres to the north, the doctors said.

Some of the wounded already at the hospital were also evacuated. At least five ambulances with flashing lights and sirens blaring could be seen driving north out of Ajdabiya before noon.

Dozens of explosions from incoming artillery fire could be heard south of the town, and fighters said there were at least 100 blasts throughout the morning.

Barrage of rockets

The rebels responded with a barrage of Grad rockets, their flames streaming upward against the backdrop of a sky darkened by the sandstorm, which often reduced visibility to just a few hundred metres and gave Gaddafi’s troops cover to advance rapidly on Ajdabiya.

Rebels have arrested those they claim are collaborating with Gaddafi forces [Evan Hill]

The bombardment from regime forces hit near the town’s large, green western gate - a landmark and rallying point for rebel forces - but shells also landed on residential areas, said Muhammad Barwuin, a rebel fighter. No civilians were reported to have been hurt in the attack.

Just 10 days ago, women and children had begun to return to Ajdabiya, and businesses started to reopen. But on Sunday, the town, which has traded hands multiple times in the months-long conflict, was deserted, and only fighters walked its shattered streets.

Shortly after noon, more than 30 vehicles carrying rebel reinforcements streamed into Ajdabiya, carrying a by-now familiar assortment of jury-rigged weaponry: machine guns, recoilless rifles, anti-aircraft batteries, and dismounted helicopter rocket pods, all welded to the back of pick-up trucks.

After the bombardment lifted, small arms fire echoed from deeper inside the town, and the government troops involved in the attack apparently withdrew. Rebels took up defensive positions around Ajdabiya and erected roadblocks made of rocks and metal sheets at most major intersections.

At the roundabout connecting two main roads, Tripoli and Bridge streets, rebels standing on the back of pickups stared attentively down the barrels of their machine guns, and an array of mounted rocket launchers pointed west.

Defensive line

Fighters also organised a defensive line along the southern edge of town, where they feared a counterattack from another major road that connects Ajdabiya to oil fields and towns to the south, where regime forces are rumoured to assemble.

Some fighters wore new, black body armour, while others have been seen carrying more advanced communications equipment, apparently supplied by the United Kingdom and Qatar.

But there was no evidence of any new weaponry, despite reports that rebels have begun using MILAN anti-tank rockets and a pledge from Qatar to provide them with similar weapons.

Supplies for the rebel army apparently remained tenuous. Several fighters said they were still primarily using rocket-propelled grenades and AK-47s. Some men have not eaten a full meal in days, and the frontlines needed fresh bread and water, one fighter on Bridge Street said.

There are also fears that Gaddafi’s forces, in the form of paid collaborators and ex-regime informants, continue to infiltrate rebel lines. Around midday, rebel cars arrived at a checkpoint east of Ajdabiya carrying a man who fighters said had been caught trying to steal a rebel vehicle.

They claimed the man wasn’t from Libya – like many suspected mercenaries and others singled out for arrest and violence by Libyans in the east, he was accused of coming from a neighbouring sub-Saharan country.

The rebels claimed two other suspected thieves had been arrested on Saturday and that they confessed to being paid a daily rate of 500 to 1,000 Libyan dinars ($414-$827) by Gaddafi’s forces to steal rebel cars, provide their location to loyalist troops, and sometimes open fire on them to sow chaos.

Several of the assembled fighters punched and kicked the man as he was loaded into the back of a sport utility vehicle that eventually drove off.

The rebels said he would be sent to Benghazi and would be appointed a lawyer by the opposition council.

Misurata besieged

In western Libya, fierce fighting continued for control of the country's third-largest city, Misurata.

At least six people were killed there in artillery fire on Sunday morning, with some 47 more injured. In the previous day's fighting, Misurata's food industry facilities were reportedly damaged.

Reporting from inside the city, Al Jazeera's Jonah Hull said a frontline cut the city in half with defenders appearing to be gaining ground.

A children's clinic has been transformed into a field hospital for wounded fighters and civilians, following the destruction of the main hospital several weeks ago, our correspondent said.

Khalid Abu Falgha, a spokesman for the clinic, said that on some days doctors had lost count of the number of wounded they had treated.

Some 99 Misurata residents were transported out of the besieged city overnight by Doctors Without Borders, arriving in the southern Tunisian port of Zarzis.

The group comprised of people injured in shelling and street fighting. It also included 64 people with serious injuries, and 10 patients in critical condition.

An International Committee of the Red Cross team is now in the city to assess the situation there, nearly a week after Libyan officials reportedly said that opening an aid corridor to the city would constitute "an act of war".