Police arrested a 12-year-old boy on the Fourth of July in Waimanalo for lighting a homemade explosive device and for possession of automatic firearms, silencers and other prohibited weapons, police said.

Responding to a 3:28 p.m. call July 4 about explosives going off, police found the Waimanalo boy in possession of two more devices. Police Special Services units were called in and recovered the unexploded devices. The boy was arrested without incident.