(Updates with killing of Muslim cleric) GAZA, March 30 (Reuters) - Explosives detonated accidentally at a training camp used by Hamas's armed wing in the southern Gaza Strip on Friday, killing one person and wounding at least 10 others, local residents said. A Hamas source in the area told Reuters that the blast was the result of a "work accident" in which an explosive device went off accidentally during training at a facility in the village of al-Qarara near the impoverished town of Khan Younis. The source identified the dead man as 21-year-old Kamel Musa, a Hamas militant. An Israeli army spokeswoman confirmed that the Israeli military was not involved. Later, a Muslim cleric was shot and killed by unknown gunmen as he was leaving a mosque at the end of prayers in Gaza City, local residents and medical staff said. The 35-year-old cleric was not known to have any political affiliation and the motive for his killing was unclear.