An explosion ripped through an apartment block in Lebanon's northern city of Tripoli on Saturday, killing two people and wounding 17, medical sources said.

It was not immediately clear what caused the blast in the city's Bab Tibbaneh area, where nine people were killed in clashes that erupted on Sunday between Sunni supporters of the government and Allawite followers of the opposition.

Tripoli is dominated by Lebanon's anti-Syrian, Sunni-led majority coalition. The Alawites, whose faith is an offshoot of Shi'ite Islam, have close ties to Syria and the Lebanese opposition, which is led by the Shi'ite Hezbollah group.

A Qatari-mediated accord in May ended 18 months of political conflict between the governing coalition and the opposition.

The standoff led to a violent showdown that threatened a new civil war. Since then there have been frequent minor security incidents.-Reuters