A hand grenade a 16-year-old boy was toying with exploded outside a mosque as worshippers were leaving Friday prayers in a Palestinian refugee camp in northern Lebanon, injuring eight, the state-run news agency and Palestinian officials said. Palestinian officials in the Baddawi camp, home to 20,000 Palestinian refugees just outside the northern port city of Tripoli, said the eight people were slightly wounded and treated at a hospital. The boy, Izzat Ahmed, was not hurt in the accidental explosion, the officials and the news agency said. The Palestinian officials said the boy panicked and tossed the grenade when its detonator was released as he was handling it. Guns and grenades are readily available in some of the 12 Palestinian refugee camps, where Lebanese authorities have no jurisdiction. Gunfights among rival guerrilla factions are common in the camps, home to about 350,000 Palestinian refugees.