The officials say at least 10 others were wounded in today's fighting in Mieh Mieh, which broke out between supporters of a former commander of the mainstream Palestinian group Fatah and members of a rival armed group, Ansarullah.
The officials say heavy machineguns and rocket propelled grenades were used in the fighting. They spoke on condition of anonymity in line with regulations.
Fighting between rival groups is common across Lebanon's 12 Palestinian refugee camps.