TRIPOLI, Lebanon - Five people were killed and nearly 20 wounded in sectarian clashes in the northern Lebanese city of Tripoli on Monday linked to unrest in neighbouring Syria, a security official told AFP.

He said four men died in the neighbourhood of Jabal Mohsen, populated mainly by members of the minority Alawite sect, an offshoot of Shias to which Syrian President Bashar al-Assad also belongs.

A fifth person was killed near Bab al-Tebbaneh, a neighbourhood of the port city located opposite Jabal Mohsen and populated mainly by Sunnis opposed to Assad’s regime. Heavy automatic weapons and rocket-propelled grenade fire was heard in the two districts throughout Monday, an AFP correspondent said. Battles first erupted on Saturday between residents of the rival neighbourhoods after security forces arrested Shadi al-Mawlawi, a Sunni Islamist, on charges of belonging to a terrorist organisation. Mawlawi’s supporters say he was targeted because of his help for Syrian refugees fleeing to Lebanon.

Some 500 of them blocked a main road leading into Tripoli on Monday and said they would leave only after Mawlawi was released.

“We will stop when Shadi is freed,” said Abdel Qader Hamid, a security guard at a Salafist Mosque in Tripoli. “If the army tries to force us to leave, we will defend ourselves even if 100 of us have to die.” Tripoli MP Mouin Mereebi said the situation was getting out of control in the city and accused the army of failing to intervene to please the regime in Damascus. “The army does not want to intervene without political cover,” he told AFP. “Tripoli MPs have urged them to enter the areas (of clashes), telling them we would walk in front of them, but they refused.”

Some security branches in Lebanon were clearly acting in collusion with Assad’s regime in a bid to prevent Tripoli from becoming a safe haven for Syrian refugees, he charged.

A total of eight people, including a soldier hit by sniper fire, have died in the port city and dozens have been wounded since the fighting began.

The army said in a statement that two soldiers were wounded on Sunday night when their patrol came under attack by armed men as they were trying to reopen a freeway between the two neighbourhoods.

The fighting has forced all businesses and shops in and around the area where the clashes are taking places to stay closed. Many residents fled at the weekend and those who stayed behind were hiding in their homes.

Prime Minister Najib Mikati, a Sunni Muslim from Tripoli, met with religious leaders in the city on Sunday and appealed for calm. Meetings between the army, politicians and religious leaders were also held on Monday.

A security official told AFP on condition of anonymity that the situation would eventually calm down but warned that the streets of Tripoli were “seething with anger.”

Since the outbreak of the revolt in Syria in March 2011, a spillover has been feared in Lebanon, where the government is dominated by a pro-Damascus coalition led by the powerful Shiite group Hezbollah.

Tripoli is a conservative mainly Sunni town where many activists and opponents of the Syrian regime have sought refuge.

Syrian authorities have repeatedly charged that arms and fighters are being smuggled in from Lebanon to help the rebels fighting to overthrow Assad.