DETROIT -- A 4-year-old girl accidentally shot and killed her 4-year-old cousin with a rifle she found under a bed at their grandfather's U.S. home, police said Friday.

The girl was playing and watching TV on Thursday with the boy when she found the gun, Detroit police Sgt. Michael Woody said. He said she pointed it at the boy and shot him once in the chest.

The boy was taken to a hospital, where he was pronounced dead, Woody said.

An adult family friend was at the home with the children at the time, he said. It wasn't immediately known who owns the gun.

The Wayne County prosecutor's office will determine whether charges should be brought, Woody said.

"It's a tragic incident," Woody told The Associated Press. "It's really not anything more than that. There was no malicious intent. There was nothing there to suggest that the grandfather put those children in harm's way, but the investigation will continue."

The boy's name wasn't immediately released.

Woody said the shooting reinforces the need for those with guns to keep them secure.

"This is a very senseless ... incident that could have been avoided," he said.