Clashes erupted late Wednesday in Beirut between gunmen from Lebanese Shiite movement Amal and the Sunni Muslim Ahbash faction, a security source said.
A personal dispute between the groups quickly spiralled into armed clashes and then spread to the streets of Beirut's Barbour area, DPA reported. The army was forced to intervene to contain the fighting, the source said.
A similar clash in August between members of Ahbash and Hezbollah, allies of Amal, near Barbour led to three deaths.
Tensions have been heightened in Lebanon over reports that a UN tribunal could indict Hezbollah in the 2005 assassination of former prime minister Rafik Hariri, a Sunni Muslim and father of the current premier.