BEIRUT (AFP) - - Hezbollah gunmen seized control of west Beirut on Friday after a third day of battles with pro-government foes in the Lebanese capital pushed the nation dangerously close to all-out civil war.

The sectarian fighting had eased by early afternoon as the army and police moved across areas now in the hands of Shiite opposition forces who routed Sunni militants loyal to the Western-backed government.

"There are no clashes anymore because no one is standing in the way of the opposition forces," a security official said on condition of anonymity.

The rattle of gunfire and the thump of exploding rocket-propelled grenades rang out across mainly Muslim west Beirut during much of the morning as Sunni government loyalists fought street battles with Shiite gunmen.

At least 11 people have been killed and dozens wounded in the fighting that erupted on Thursday after Hezbollah chief Hassan Nasrallah said a government crackdown on his Iranian- and Syrian-backed group was a declaration of war.

The unrest triggered urgent international appeals for calm amid fears that the protracted political feud could plunge the divided multi-confessional nation back to the dark days of the 1975-1990 civil war.

Beirut residents were fleeing for shelter elsewhere as tanks rolled through the streets and hundreds of riot police and troops patrolled the city, but did not get involved in the fighting.

Lebanon was largely cut off from the outside world, with the international airport and Beirut port shut and some roads to neighbouring Syria blockaded by burning tyres.

Arab nations led by regional powerhouse Saudi Arabia are pushing for a special session of foreign ministers to tackle the crisis and some Middle East states have begun trying to evacuating residents.

President Shimon Peres of Israel -- whose country fought a devastating war against Hezbollah in 2006 -- claimed the violence was fomented by Iran to further what he said was Tehran's goal to control all of the Middle East.

In Damascus, Syrian President Bashar al-Assad -- whose country is Iran's closest regional ally -- said the unrest was a purely "internal affair."

Witnesses reported fierce gunbattles in several parts of west Beirut as the Sunni neighourhoods considered bastions of Lebanon's ruling bloc fell to militants from Hezbollah and its ally Amal.

"Everyone is running away," said 35-year-old businessman Imad as people rushed to stores that remained open to stock up, while others remained trapped in their homes by the fighting.

"It was a hellish night. The armed militants were everywhere shooting all over the place," said Rima, another west Beirut resident.

Hezbollah, the most powerful armed movement in Lebanon, has also forced the shutdown of all media belonging to the family of parliamentary majority leader Saad Hariri, while a rocket hit the outer perimeter of his Beirut residence.

Hariri, whose father Rafiq Hariri was assassinated in 2005, had made a television appeal to try to calm the situation but this was rejected by Hezbollah.

Gunmen firing rocket-propelled grenades surrounded the headquarters of the Hariri's Future Television and his movement's Al-Mustaqbal newspaper early Friday, forcing all its media outlets to close.

"The army is in control of institutions placed under its authority, such as the media outlets of the Future Movement," the army said.

"It also controls the area around the government headquarters, the central bank, major roads and the area where Hariri and Jumblatt's residences are located in west Beirut," referring to prominent Druze leader Walid Jumblatt.

Air traffic was paralysed for the third straight day with no flights scheduled to land or take off from Beirut international airport, an airport official said, after Hezbollah supporters blocked access with mounds of earth and burning tyres.

Nasrallah delivered his defiant speech on Thursday after the government launched a probe into a private communications network run by Hezbollah, which is seen in the West as a terrorist outfit and which critics say has become a "state within a state."

"The decisions are tantamount to a declaration of war and the start of a war... on behalf of the United States and Israel," Nasrallah charged. "The hand that touches the weapons of the resistance will be cut off."

The United States delivered a blunt warning to Hezbollah to stop its "disruptive activities" while UN Security Council members said they were "deeply concerned" over the crisis, a view reflected by other Arab and European leaders.

The crisis will be the focus of talks between President George W. Bush and Lebanese Prime Minister Fuad Siniora in Egypt next week during the US leader's tour of the Middle East.

Regional powerhouse Saudi Arabia, which backs the Siniora government, called for an urgent meeting of Arab foreign ministers, while Yemen suggested army chief Michel Sleiman be mandated to chair a dialogue to resolve the crisis.

The long-running political standoff, which first erupted in November 2006 when six pro-Syrian ministers quit the cabinet, has left the country without a president since November, when pro-Syrian Emile Lahoud stepped down.

While the rival factions have agreed on Sleiman as a consensus candidate, they disagree on the make-up of the new cabinet and so far 18 sessions of parliament to choose a president have been cancelled.