By Yvonne Bell
ZAWIYAH, Libya (Reuters)- - Fierce fighting broke out on Friday in the Libyan city of Zawiyah, Reuters witnesses said, in an apparent counter-offensive by Muammar Gaddafi's forces against rebels advancing toward Tripoli.
Sustained blasts from rocket-propelled grenades, mortars and anti-aircraft guns were heard from the direction of Zawiyah's central square as a black column of smoke rose into the evening sky, the reporters on the outskirts of the city said.
Rebels had seized the city and its coastal oil refinery from Gaddafi's forces earlier this week, giving them control of part of the main highway between Tripoli and Tunisia as well as a key source of fuel to the capital.
The rebels seized another nearby town on Friday, extending their grip on the strategic coastal highway.
Gaddafi's prime minister said on Thursday the government would overcome the rebel uprising in "a few days."
Recent rebel advances have isolated the Libyan capital and trapped thousands of foreigners in Tripoli, who will be evacuated in a massive international rescue, probably by sea, an international body said on Friday.
With the rebels making advances on the ground, NATO continued its campaign from the air, alliance war planes pounding targets in the capital overnight.
Libyan officials brought journalists to a residential district where a compound of several large buildings was blasted to pieces. Neighbours said it belonged to Abdullah al-Senussi, Gaddafi's brother-in-law and head of intelligence.
In another sign the fighting is hitting closer to Gaddafi's inner circle, the brother of the spokesman who has served as the Tripoli government's public face was reported killed in a front line city. The government blamed NATO attack helicopters.
NBC News reported on Friday that Gaddafi was making preparations to leave Libya with his family, for possible exile in Tunisia, but that it was unclear if he would follow through. NBC said the information came from U.S. officials who cited intelligence reports.
East of the capital, where fighting has been bloody and advances slow, rebels launched an assault on Friday but were taking heavy casualties, a Reuters reporter there said.
A spokeswoman for the International Organization for Migration (IOM), Jemini Pandya, said the operation to rescue thousands of Egyptians and other foreigners trapped in Tripoli by the latest fighting would begin within days.
"We are looking at all options available, but it will probably have to be by sea," she told a Geneva news conference.
More than 600,000 of an estimated 1.5 million to 2.5 million foreigners, mostly Asian and African migrant workers, have fled Libya in six months of fighting. However, many thousands remained in Tripoli, which until this week was far from fighting and a safe two-hour drive from the Tunisian border.
That route has been cut since the rebels entered Zawiyah, which straddles the coastal highway, six days ago. On Thursday they took the neighboring town of Sabratha, and on Friday they seized the nearby town of Surman.
Several hundred rebels and rebel supporters were gathered on the streets of Surman, just off the highway, to celebrate the victory, flying the rebel green, red and black flag.
"SENUSSI HOUSE" HIT
In Tripoli, Omar Masood, an oil engineer who lives across the street from the compound that was destroyed, said it had been struck before dawn and belonged to Senussi, one of the most senior figures in Gaddafi's leadership.
Neighbours and Libyan officials said one guard, from India, had been killed. Officials could not comment on whether it was Senussi's house or whether he was present at the time.
A large building had been reduced to rubble. The grounds appeared to be grand, with a fountain and children's swing set and a garden with a live gazelle standing amid the ruins.
Senussi, who is married to Gaddafi's sister, is one of three figures along with Gaddafi and his son Saif al-Islam wanted by the International Criminal Court in the Hague for war crimes. The court's prosecutor blames him for killing civilians.
"Even if he was someone from the intelligence, it wouldn't justify an attack on a residential house," said Aref Fahim Ahmed, another neighbor. NATO says it is bombing military targets to protect civilians.
A government official said the brother of Moussa Ibrahim -- the spokesman whose briefings have been broadcast worldwide throughout the six-month-old uprising -- was killed by a NATO helicopter gunship in the central square of Zawiyah.
The 25-year-old student, Hasan Ali, had gone there with a group of others to check on friends, the official said.
Ibrahim, who has repeatedly denied reports of rebel advances, said on state television on Thursday: "We reassure people that we are making progress on all fronts." According to the JANA news agency, he promised all Libyans payments of 500 dinars, about $300, as reward for being steadfast.
East of Tripoli the rebels have failed to match their recent breakthroughs to the west. A Reuters reporter at the front said rebels had launched an assault on Gaddafi's forces in Zlitan, the closest front line east of the capital. Many wounded were being brought to the rebels' field hospital.
"Battles began in the early hours of today and the rebels have liberated most of Zlitan," rebel spokesman Gemal Salem told Reuters by telephone. "Now the fighting is in the west of Zlitan. We have lost 32 rebels and 150 wounded."
West of Tripoli, rebel fighters held meetings on Friday with local leaders in Sabratha a day after capturing it. The ancient Roman town, a UNESCO World Heritage site, was quiet.
Rebels also seized Garyan this week, a town which straddles the main route to the capital from the south. A Reuters reporter there said it was largely quiet on Friday, although gunfire could be heard in the distance. Hospital officials said one rebel had died and three were seriously hurt the previous day in clashes with Gaddafi troops west of the town.
(Additional reporting by Missy Ryan in Tripoli; Robert Birsel in Benghazi, Libya; Stephanie Nebehay in Geneva; Ulf Laessing in Garyan, Libya; Mariam Karouny in Beirut; William Maclean in London; and Souhail Karam in Rabat; Writing by Richard Valdmanis and Peter Graff; Editing by Jon Boyle)
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