A Lebanese soldier was killed and three others were critically injured in a bomb explosion Saturday in a Palestinian refugee camp in northern Lebanon, a senior military official said. The official, speaking on condition of anonymity because he was not allowed to give statements to media, said the blast occurred as the army was dismantling bombs and land mines in the Nahr el-Bared camp, the scene of a month long battle between the military and al-Qaida-inspired fighters holed up inside. Saturday's death brings to 77 the number of soldiers killed. More than 150 have been wounded since fighting erupted May 20 between the Lebanese troops and Fatah Islam militants in this camp near the port city of Tripoli. After Lebanese Defense Minister Elias Murr declared victory over the militants on Thursday, the army has been mopping up segments of the camp under its control.