Police have arrested an 85-year-old man after an explosion in suburban Tampa Bay damaged a home and rattled residents.

Authorities say Tarpon Springs residents reported a loud bang at a home early Monday morning. The Tampa regional bomb squad was called in to investigate and found a hand grenade had detonated in the home's backyard. The blast damaged the home, shattering rear windows and breaking concrete. Police say four people inside the home were not hurt.

Police executed a search warrant on a neighbor's home and found military-grade explosives, including anti-personnel mines, a shotgun and a hand grenade.

Police say the man was arrested and charged with possession of a weapon as a convicted felon but has not been charged in connection with the explosion.