The Lebanese army deployed on Saturday to halt two days of heavy sectarian fighting in the northern city of Tripoli which medical sources said had killed nine people.

Soldiers, backed by armoured vehicles, took up positions between Sunni and Alawite districts of the city in an effort to stop clashes which have wounded at least 68 people and forced residents to flee their homes. The sides exchanged heavy grenade and machinegun fire until dawn.

In the past two months, at least 22 people have been killed in the predominantly Sunni city in sectarian fighting blamed by politicians and analysts on political turbulence in Lebanon.

The Lebanese army, which often takes on a policing role, said in a statement it would not tolerate any security violations "even if that requires the use of force in all its means". One soldier was among the wounded.

The dead included a woman, a boy and a man who was struck by a rocket-propelled grenade while driving his taxi.

"It's unacceptable for Tripoli and its poor and deprived districts to keep paying the price of escalating internal political crisis," Economy Minister Mohammed Safadi, a Sunni politician from Tripoli, said in a statement.

The bouts of violence in the city since late June have been linked to lingering disputes between the Sunni-led parliamentary majority bloc and a rival alliance led by Shi'ite Hezbollah, which is close to Alawite groups in the north.

A protracted political conflict between the sides was largely resolved in May by a Qatari-mediated deal.

But they are now at odds over the policy statement of a national unity government which was finally formed on July 11 after weeks of wrangling over portfolios.

Language in the policy statement regarding Hezbollah's guerrilla army is the main area of disagreement.

Hezbollah, which is backed by Syria and Iran, used its weapons in May to briefly seize Beirut and rout supporters of the anti-Damascus majority bloc.

The move helped Hezbollah impose the opposition's terms for a settlement with rivals including Sunni politician Saad al-Hariri -- a strong opponent of Syrian influence in Lebanon who has wide influence in Tripoli.

The Alawite faith is a small offshoot of Shi'ite Islam and its adherents are mostly based in Syria which is ruled by President Bashar al-Assad, himself an Alawite.

Their numbers are small in Lebanon but they gained some political influence during an era of Syrian dominance that came to an end in 2005 after international pressure forced Damascus to withdraw troops from the country.