Forces loyal to Muammar Gaddafi, the Libyan leader, have continued a large-scale military offensive against opposition fighters in the country's east, launching air strikes at the oil-producing towns of Ras Lanuf and Brega.

Opposition forces were reported to be retreating from Ras Lanuf. They lost control of the pockets of residential parts of the town that they had been clinging to by Friday morning, sources told Al Jazeera. They are, however, fighting back in the northeastern part of the city, where pro-Gaddafi forces are attempting to enter.
Plumes of smoke were seeing billowing from an oil installation in the city, reportedly the result of military air strikes. Earlier in the day, Ibrahim Said, the deputy director of the hospital in nearby Ajdabiya, said that rebels were still in control of the strategically important oil refineries and storage depots in Ras Lanuf.
Ibrahim al-Alwani, a rebel fighter, said he and comrades still in Ras Lanuf had seen government troops in the town centre.
“I saw maybe 150 men and three tanks,” he told Reuters on Friday morning. “I can hear clashes.”
The government troops had landed by boat near the Fadeel hotel in Ras Lanuf on Friday, a spokesperson told Reuters.
“Four boats carrying 40 to 50 men each landed there. We are fighting them right now,” Mohammed al-Mughrabi said. Rebels appear to have withdrawn to their last main checkpoint, about 15km to the east of the town's centre.
“They came from the air, they came from the sea, and there were rockets everywhere. It was a big surprise for us,'' one rebel fighter, Mustafa Mehrik, a 39-year-old coffeeshop owner, said in Brega, a rebel-held town to the west where many of the casualties from the attack were taken.
“Everyone is worried. Today they say there will bring heavy weapons from Benghazi.''
Foreign journalists faced significant hurdles getting information out of Ras Lanuf, but Libyan state television aired footage on Friday of people fleeing the city and of pro-Gaddafi forces searching houses for weapons.
Intense fighting
Pro- and anti-government forces are locked in intense fighting for control of several other cities and towns along the coastline to the east of Tripoli, including Bin Jawad. In Az Zawiyah, to the west of Tripoli, the revolt appeared all but crushed, witnesses said. An oil refinery there has resumed operations, according to an official.
It appears that with fresh clashes reported in Misurata, Ras Lanuf and Brega, the frontline is now advancing eastwards, towards Benghazi, a rebel stronghold.
Benghazi was the place where the protests against Gaddafi first began last month, quickly escalating into a a mass uprising against his more than 41-year-old rule.
Hoda Abdel-Hamid, Al Jazeera's correspondent in Benghazi, said that thousands of people had gathered there on Friday in support of the rebel forces, expressing optimism that they could hold on to the city if attacked by Gaddafi's military.
“Many people have died in our struggle in Ras Lanuf and in Benghazi, but the youth has chosen to fight on rather than see this rule continue, and they will fight for the sake of God,” a blind imam proclaimed ahead of Friday prayers.
“But if you look at the country and what's happening ... the Gaddafi forces are certainly trying to keep or to regain control of all the oil facilities around the country,” Abdel-Hamid reported.
For Gaddafi's forces to retake Tobruk, Libya's eastern-most oil port, they would have to pass through Benghazi, she said.
Benghazi has been serving as a rear support base for many rebels travelling to and from the front lines.
Abdel-Hamid reported that if Ras Lanuf was lost entirely, it would likely strike a strong blow to the rebels' morale. The rebels readily admit that they do not have the firepower to counter the pro-Gaddafi forces, she added.
Photo: Shrapnels fly through the air as a tank shell explodes near Libyan opposition fighters defending their last position against Muammar Gaddafi's loyalist forces in Ras Lanuf on March 10, 2011. (Getty Images)