By Maria Golovnina and Mohammed Abbas
TRIPOLI/BIN JAWAD, Libya (Reuters) - Libyan government forces launched fierce attacks on the western rebel stronghold of Zawiyah on Saturday, while in the east, rebels advanced on Muammar Gaddafi's home town of Sirte.
Fighters in Zawiyah, just 50 km (30 miles) west of Tripoli, repelled two attacks by pro-Gaddafi forces who used tanks and artillery. Dozens of rebels armed with rifles manned rooftops, watching nearby streets from behind piles of sandbags. Roads and side streets were barricaded with rebel checkpoints.
"After the morning attack they attacked again. They entered from the west and started shooting rockets at buildings in the square," rebel spokesman Youssef Shagan said by telephone.
"We are in a good position ... They will attack again at night, we think."
A doctor in Zawiyah said at least 30 people, mostly civilians, had been killed during fighting in the day, bringing to at least 60 the death toll from two days of battles.
Abu Akeel, a Zawiyah resident, told Reuters that government forces had shelled houses and fired on a mosque where people were taking shelter. Another resident said he saw more than 20 tanks advance across the main square during the second assault.
One resident, Ali, said sporadic fighting after dusk had subsided by late evening. "It is calm but we are afraid," he told Reuters by phone. "We are waiting because there could be another assault. They are still around us."
People opposed to Gaddafi's 41-year rule have been fighting his forces in Zawiyah for more than a week, after rebels took over large parts of eastern Libya in an uprising inspired by the overthrow of veteran rulers in Egypt and Tunisia this year.
In Tripoli, Deputy Foreign Minister Khaled Kaim told reporters Zawiyah was "quiet and peaceful" late on Saturday. "We hope by tomorrow morning life will be back to normal."
The doctor said Gaddafi's tanks had fired at residential buildings and civilian cars trying to flee.
"There is a lot of destruction in the city, I look around and all I see is destruction. Bombed buildings and burning cars everywhere -- I cannot even count how many," he said.
One fighter vowed to fight to the death.
"Gaddafi will never enter this city. He will never set foot here. The only way for him to enter the city is when we are all dead. He has to kill us all to control the city," the rebel, who gave his name as Ibrahim, said by telephone.
Rebels in eastern Libya said they were pushing further west after driving forces loyal to Gaddafi from the oil town of Ras Lanuf on Friday.
Doctors said at least 26 people had died in Friday's fighting around Ras Lanuf, and what rebels said was an attack by Gaddafi's forces on an arms store on the edge of the eastern town of Benghazi, where the uprising began in mid-February.
Rebel fighters took the town of Bin Jawad, some 525 km east of Tripoli, and were moving on toward Sirte, Gaddafi's heavily guarded home town, 160 km (100 miles) away.
In Bin Jawad, rebels played the pre-Gaddafi monarchist national anthem over a loudspeaker. Government fighter jets and a helicopter circled overhead but did not open fire, although the rebels fired at the helicopter with anti-aircraft guns.
A Reuters correspondent was shown the wreckage of a warplane, and the bodies of two crew, that rebels said they had shot down on Saturday near Ras Lanuf.
Mohammed Abbas, in a brief message from the scene, said he was shown a Sudanese passport that he was told belonged to the pilot, giving his occupation as accountant.
Rebels have accused Gaddafi of using African mercenaries to fight for him.
Buoyed by eastern successes, some rebels said an attack on Sirte was imminent. But others were wary of the limitations of a rebel force made up of soldiers who have deserted from Gaddafi's ranks and volunteers who have more enthusiasm than experience.
"We're going to attack Sirte, now," rebel fighter Mohamed Salim told Reuters, while another fighter, Mohamed Fathi, said: "Listen, we have no organization and no military plan. We go where we're needed." Both were on the way to Bin Jawad.
Where many eastern towns have fallen with little resistance, Sirte may prove a tougher prospect. It has long received hefty handouts from Gaddafi, who liked to host Arab and other international conferences in the coastal city.
Sirte is also the site of a major air base and home to military forces loyal to Gaddafi.
"If Benghazi (rebels) can expand down into the Gulf of Sirte ... they've got a very good shot at independence at the least -- or maybe even overturning him at the most," said Peter Zeihan, analyst with the U.S.-based Stratfor think tank.
The opposition, while it has assembled a loose fighting force, has failed to produce a clear leadership, a weakness Gaddafi clearly hopes to exploit as the struggle continues.
In Benghazi, eastern heartland of the insurrection, the opposition National Libyan Council said it had named a three-member crisis committee, including a head of military affairs and foreign affairs. Its head told Al Jazeera television it expected to be formally recognized soon by some countries.
The revolt is the bloodiest yet against long-entrenched rulers in the Middle East and North Africa. Brega and Ajdabiyah, eastern oil towns in rebel hands, have both been fired on from the air in the past few days.
The International Energy Agency said the revolt had blocked about 60 percent of Libya's 1.6 million bpd (barrels per day) oil output. The drop, due largely to the flight of thousands of foreign oil workers, will batter the economy.
Libyan crude exports are set to slide in the coming days.
"You now have a situation where everything is pointing toward a more or less complete shutdown of Libyan production," said Samuel Ciszuk, a senior analyst with IHS Energy.
U.S. crude prices have risen to their highest levels since September 2008, and Brent crude futures for April delivery closed at $115.97 a barrel on Friday, up $1.18.
(Additional reporting by Michael Georgy in Tripoli, Alexander Dziadosz in Ajdabiya, Mohammed Abbas in Bin Jawad and Tom Pfeiffer in Benghazi; Writing by Philippa Fletcher and Ralph Boulton; Editing by Kevin Liffey)