Three people were killed in clashes between the Sunni neighborhood of Bab El-Tebbaneh and Alawite Jabal Mohsen on Wednesday in Lebanon's northern port city of Tripoli.

A security source told Xinhua that the clashes erupted after the killing of an Alawite citizen by unknown gunmen while driving a car in the Bab El Tebbaneh neighborhood. The car hit a woman who died later of her wound.

The source added that heavy gunfire and the explosion of a mortar shell broke out in Bab El-Tebbaneh, which killed an 11-year- old boy.

The Lebanese army deployed in the area swiftly separated the rival groups and closed the main highway linking Tripoli to the northern regions.

A cautious calm is seen on the front lines between the two feuding neighborhoods as the 11-day violence has killed 25 people and injured more than 132 others, including 26 soldiers.

Since Syrian rebels took up arms to fight against President Bashar Assad in 2011, the Lebanese port city has witnessed violent clashes between the Sunni neighborhood that backs the rebels and the Alawite neighborhood that supports the Syrian regime.

The Lebanese government announced in November 2013 a security plan to restore calm to the northern city and then decided in December 2013 to deploy the army in the city for six months.