The Libyan government rejected ceasefire conditions set out by opposition leaders on Friday and described coalition air strikes against it as a "crime against humanity".
The government spokesman, Mussa Ibrahim said government troops would not leave Libyan cities as demanded by the opposition.
"They are asking us to withdraw from our own cities. .... If this is not mad then I don't know what this is. We will not leave out cities," said Ibrahim, the government spokesman.
He described coalition air strikes against it as a "crime against humanity", saying at least six civilians were killed in an attack on a village in the east of the country.
"Some mad and criminal prime ministers and presidents of Europe are leading a crusade against an Arab Muslim nation," Ibrahim, told reporters.
"Sounds familiar? ... It's a crime against humanity."
He said six civilians were killed and dozens wounded in an attack on a village near the eastern city of Brega on Thursday. "You cannot get more civilian than this (village)," he said.
Earlier, forces loyal to Libyan leader Muammar Gaddafi mounted an intense artillery bombardment of fighters-held Misrata and pro-Gaddafi troops attacked shops and homes in the city center, a fighter-opposition spokesman said.
Misrata is the last big fighters stronghold in western Libya but after weeks of shelling and encirclement, government forces appear to be gradually loosening the fighters' hold on the city, despite Western air strikes on pro-Gaddafi targets there.
"They used tanks, rocket-propelled grenades, mortar rounds and other projectiles to hit the city today. It was a random and very intense bombardment," the spokesman, called Sami, told Reuters by telephone. "We no longer recognise the place. The destruction cannot be described."
"The pro-Gaddafi soldiers who made it inside the city through Tripoli Street are pillaging the place, the shops, even homes, and destroying everything in the process."
"They are targeting everyone, including civilians' homes. I don't know what to say, may Allah help us," he said.
Accounts from Misrata, Libya's third biggest city about 200 km (130 miles) east of Tripoli, could not be independently verified because Libyan authorities have not allowed journalist to report freely from the city.
A resident in the city told Reuters in an email that the 32nd Brigade, one of the best-equipped and trained units in the Libyan armed forces, had been sent in to Misrata early on Friday with the aim of occupying the city.
"So the question is where is the international community?" he said.
Libyan anti-Gaddafi forces were digging in Friday in their battle with Gaddafi forces for the oil town of Brega as leaders admitted they were ready for a ceasefire under the right conditions.
But the West backed off from arming the rag-tag band of fighters and pushed for a political solution instead.
An AFP correspondent citing anti-Gaddafi forces commanders said fighting had erupted around Brega, about 800 kilometers (500 miles) east of Tripoli Friday morning.
Opposition fighters prevented reporters and civilians from leaving the strategic town of Ajdabiya for Brega, about 80 kilometers (50 miles) to the west, but it was unclear exactly where the frontline was or who controlled the refinery town.
The fighters had the previous day been beaten back by heavy shelling from Gaddafi’s forces when they launched a counter-offensive at Brega in a bid to resume their march on Tripoli, started soon after the uprising against the hardliner's rule was launched on February 15.
The opposition is ready for a ceasefire provided Gaddafi’s forces end their assaults on fighters-held cities, Transitional National Council leader Mustafa Abdul Jalil said Friday.
"We agree on a ceasefire on the condition that our brothers in the western cities have freedom of expression and also that the forces that are besieging the cities withdraw," Jalil told reporters in Benghazi after meeting Abdul Ilah Khatib, the U.N. special envoy to Libya.
It was clear, however, that the anti-Gaddafi fighters were intent on cleaning up their act -- keeping civilians and raw recruits away from the frontline.
After weeks of near-anarchy, the Benghazi-based leaders of the insurrection seem to be putting their house in order in an attempt to combat the better-organized forces loyal to Gaddafi.
At the western entrance to Ajdabiya, a 54-year-old reservist, Abdelkarim Mansouri, explained: "We're implementing a new tactic. We don't want any more kids to die. War is not a game. These are the orders of the military council.
"You must be organized if you want to chase Gaddafi. Our army is now in control of the fighting."