Heavy clashes erupted south of Beirut yesterday between mainly Shia and Druze militants, breaking a tense calm that had taken hold after feuding factions reached a tentative agreement to end four days of fighting.

The crackle of machinegun fire and thump of exploding mortar rounds echoed through the town of Shwayfat on the lower slopes of the Chouf mountains overlooking southern Beirut as fighters from the Shia group Hezbollah and its allies fought Druze gunmen loyal to Walid Jumblatt, a key government ally.

Residents raced along otherwise empty roads to escape the fighting as Lebanese troops took cover behind sandbagged checkpoints. Thick smoke rose from several mainly Druze villages in the Chouf as Hezbollah units pressed their attack against their Druze rivals.

Sources in Hezbollah-controlled southern Beirut said that heavily armed fighters equippedwith antitank missiles were seen deploying to reinforce Hezbollah units in the Chouf.

Katyusha rocket batteries were also positioned within southern Beirut aimed at the area to provide artillery support if needed.

Fighting continued into the evening despite a 6pm ceasefire and calls for an end to hostilities by Mr Jumblatt and his Druze rival, Talal Arslan, an opposition figure. “The way that Hezbollah have used their weapons has killed the declaration that they were only to be used against Israel,” Mr Jumblatt told al-Arabiya television.

The latest upsurge of fighting dented an agreement brokered over the weekend by the Lebanese Army to end fighting between government and opposition supporters. The Lebanese Army is seen as the one neutral state institution in the country, albeit not powerful enough to stop fighting between rival factions. The army proposed on Saturday overseeing the implementation of three government decisions made last week against Hezbollah activities, which triggered the street clashes in Beirut. The Government agreed to the proposal, and the Hezbollah-led opposition said that it would withdraw its fighters from west Beirut, which they overran on Friday.

“We wanted the army to provide security for us, but what can the army do when this militia, called Hezbollah, is stronger than the army?” Mr Jumblatt asked The Times.

Mr Jumblatt has survived three decades of violence, war, intrigue, assassination attempts and shifting political alliances. A former ally of Syria, he has evolved into one of its most resolute opponents and remains Hezbollah’s harshest critic, earning the staunch enmity of the Shia group.

Sheikh Hassan Nasrallah, Hezbollah’s leader, has described the Druze leader as the true head of the Government, not Fouad Siniora, the Prime Minister. Hezbollah held him “personally responsible” for the killing of two of the party’s militants and the disappearance of a third in the Druze town of Aley, which appears to have triggered the fighting.

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