TRIPOLI, Lebanon: Fierce clashes raged between supporters and opponents of Syrian President Bashar Assad in Lebanon's second city of Tripoli Saturday night, shattering a day-old ceasefire in the latest round of fighting that has killed seven people.

Security sources said the fighting with automatic weapons, rocket-propelled grenades and mortars, erupted as Lebanese Army units were preparing to deploy in the mainly Alawite Jabal Mohsen district, where residents back Assad against rebels seeking an end to the Syrian president’s rule, security sources said.

There was no immediate word on casualties in the night-time fighting that was the heaviest in the city since the latest bout began Thursday. 

The fighting also cut off all mobile communications with the city. 

Combatants in Jabal Mohsen and their rivals in Bab al-Tabbaneh, where support for the uprising in Syria is staunch, had issued Friday separate cease-fire announcements.

Seven people, including a soldier, were killed in the three days of clashes which also left 30 others wounded.

Commenting on the unrest in the northern city, Grand Mufti Sheikh Mohammad Rashid Qabbani Saturday called for calm and urged residents of the city to cooperate with state institutions.

“Tripoli and residents in the north should enhance cooperation with each other and state institutions to avoid steering the country toward instability,” he said, according to a statement from Dar al-Fatwa.

The top Muslim figure also warned that Lebanon was passing through “critical conditions” and stressed the need to deal “wisely” with emergency issues “for the sake of maintaining the people's unity and [in order to] avert strife.”

Caretaker Interior Minister Marwan Charbel, who held a news conference in the city, also warned that the situation in Tripoli was dire and urged Parliament to take steps that could help curb violence there.

“There are some who want trouble in Lebanon, some media being among them, but there is something more important and what is happening in Tripoli is [grave] and is linked to regional [developments],” he said, in a reference to the conflict in Syria.

“We hope there will be a genuine understanding. I have faith in Speaker Nabih Berri and urge him to convene a session of Parliament to sign a pact that has the headline ‘Security in Lebanon’, particularly in Tripoli,” he added.

Residents of Bab al-Tabbaneh and Jabal Mohsen have been fighting on and off since 2008. However, tensions and clashes between both the sides have increased in frequency and intensity since the Syrian uprising began in 2011.