The front line in the battle for control of Libya's coast remained unclear on Sunday, after the western edge of Ajdabiya came under fire from a barrage of rockets.

Libyan rebels, seeking to overthrow long time leader Muammar Gaddafi, had earlier advanced from Ajdabiya toward the oil port town of Brega in the country’s east.

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But they were outflanked by Gaddafi's troops who avoided the main body of fighting in order to attack from Ajdabiya's south.

Al Jazeera's Mike Hanna, reporting from just outside Ajdabiya, said a sandstorm had prevented NATO aircraft from targeting pro-Gaddafi soldiers.

"Once you have weather conditions like this, it means that the Gaddafi forces are able to move on the highways, able to move very quickly," he told us.

"They are able to set up their artillery barrages more precisely, getting their spotters forward. This means they are much more effective in these conditions, because they do not have to worry about any air strikes from above."

But the situation may be short-lived, he said.

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"This may be temporary - this did also happen a week ago." 

The fight for Brega

Following NATO air strikes along the coastal road on Saturday, anti-Gaddafi forces said they had reached the edges of Brega, bringing engineers with them to repair the damaged oil infrastructure.

But Gaddafi's troops remain consolidated within the city centre, said rebel fighters returning to Ajdabiya in the evening.

"We have people on the edge of Brega, we control that area only," said 20-year-old Mohammed el-Misrati.

"Nothing has changed inside Brega." 

The battle for territory in Libya's east left eight anti-Gaddafi fighters dead and 16 wounded on Saturday.

"We were in our vehicles and they opened fire with rockets," said an injured fighter named Abdulrazek in Ajdabiya hospital.

Siege of Misurata tightens

Al Jazeera's Sue Turton reports from Ajdabiya

At least six people were killed on Sunday morning in Misurata, Libya's third largest city, with some 47 injured in the artillery fire. On Saturday, food industry facilities in the besieged city were reportedly damaged.

"They are trying to starve us to death, attacking the dairy, the water purification plant," Jiraal, a Libyan who returned from Britain to join anti-Gaddafi fighters, told the AFP news agency.

Some 99 Misurata residents were transported out of the besieged city overnight by the aid agency Medicins Sans Frontieres (MSF), arriving in the southern Tunisian port of Zarzis.

The group comprised of people injured in the continued shelling and street fighting. It also includes 64 people with serious injuries, and ten patients in critical condition.

Cluster bombs denied

Libyan officials categorically denied claims that forces loyal to Gaddafi have used cluster bombsin the battle for Misurata.

Tripoli authorities refuted reports from New York-based watchdog Human Rights Watch, which said its researchers had found remains of cluster munitions in the city - described as the last stronghold of anti-Gaddafi fighters in western Libya.

"Absolutely no. We can't do this. Morally, legally, we can't do this," Gaddafi spokesman Mussa Ibrahim told reporters.

"We never do it. We challenge them to prove it."

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Cluster bombs explode in the air, scattering small "bomblets" across a wide area. Many fail to detonate initially, leaving a potentially devastating minefield-like area on the ground.

"Last night it was like rain," said Misurata resident Hazam Abu Zaid, referring to cluster bombs.

Steve Goose, HRW's arms division director, said: "It's appalling that Libya is using this weapon, especially in a residential area.

"They pose a huge risk to civilians, both during attacks because of their indiscriminate nature - and afterwards because of the still-dangerous unexploded duds scattered about."

Libya has never signed the Convention on Cluster Munitions, and is therefore not bound by the international treaty.

But Adrian Traylor, an independent conflict resolution consultant, tells Al Jazeera that the material gathered by researchers in Misurata "could be used as future evidence of a crime against humanity or war crime for, at very least, an attack directed at a civilian population - regardless of the cluster weapons convention."

A Red Cross team arrived in Misurata on Saturday 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".

Source: Al Jazeera and agencies