Forces loyal to Libyan leader Muammar Gadafy tried to deny rebels in the city of Misrata their only lifeline to the outside world by shelling the port and the areas around it today, rebels and residents said.
Misrata, the biggest rebel stronghold in the west of Libya still resisting Col Gadafy's forces, is encircled on three sides and depends on its Mediterranean port - under fragile rebel control - to bring in supplies.
Col Gadafy's forces have pulled out of the centre of Misrata after weeks of shelling and gun battles failed to root out rebel fighters who harass government troops from the cover of bombed-out buildings.
But the withdrawal appears to have been only tactical, with pro-Gadafy forces positioning themselves on the edge of the city and using heavy artillery to bombard the port and the area around it in the east of Misrata.
Rebel spokesman Abdelsalam said the insurgents appeared to have held off Col Gadafy's forces in fierce fighting during which at least three people were killed and 10 wounded. A Nato air attack helped.
One resident, Mohammed Ibrahim, said the Nato planes had struck a convoy of scores of jeeps, destroying some and forcing others to retreat to the east.
Several containers were destroyed and some cars damaged in the bombardment of the port. The shelling stopped after nightfall, but it was unclear whether that was just temporary.
A rebel spokesman called Bashir said Col Gadafy's forces were using Grad missiles - Russian-made munitions fired in multiple rounds from launchers on the back of trucks - to attack the port.
Libyan officials deny killing civilians in Misrata, saying they are fighting armed gangs and al-Qaeda sympathisers who are seeking to destroy the country.
A doctor in the city, called Aimen, said Col Gadafy's forces were conducting "continuous shelling to the sea port" and that the bombardment was being done at long-range.
Misrata, Libya's third-biggest city, is about 200 km east of the capital. Hundreds of civilians and fighters have been killed there since the city rebels against Col Gadafy's rule in February, turning it into a symbol of resistance.
The Nato military alliance says it is doing what it can to protect civilians in the city but Col Gadafy's forces have split up into small units and parked their armour next to buildings, making it hard for warplanes to find clear targets.
Nato planes bombed Khoms, about halfway between Tripoli and Misrata, today, state news agency Jana said.
Misrata experienced some of the bloodiest fighting in the two-month siege at the weekend, with medics saying nearly 50 people were killed.
Witnesses described bodies lying in the streets and doctors struggling to cope with the wounded.
The Qatar-based Al Jazeera television station this afternoon broadcast live pictures from Misrata of women and children waving the green, black and red flag adopted as a symbol of the anti-Gaddafi rebellion.
Demonstrators held up photos of people they said had been kidnapped by government forces, and they said they would carry on their struggle against "the tyrant".