At least four people have been killed and dozens injured over the past two days in clashes in Lebanon's northern city of Tripoli between gunmen loyal to opposing sides in neighbouring Syria's civil war, security officials said. The fighting on Tuesday and Wednesday in the port city have pitted Sunni Muslim districts against areas housing Alawites, from the same religious community as Syrian President Bashar al-Assad. Al Jazeera's Rula Amin reports from Tripoli.