DETROIT -

A 4-year-old boy was shot and killed Thursday by his 4-year-old girl cousin on Detroit's west side.

Detroit police say the children were watching TV when they found the gun at a home on Tuxedo Street near Livernois and Grand River Avenue.

Police say several young kids were in a back room of the home playing with guns. Investigators say there was adult supervision in the home at the time but the children were alone in the back room.

The boy was shot in the chest.

"Make sure that your weapons are secure, that your children and no one else in the home can get access to the guns," said Detroit Police Cpt. Rodney Cox. "The chief and the Detroit Police Department consistently stands behind responsible gun ownership. It appears right now that this was not responsible ownership."

Neighbors tell Local 4 the boy did not live at the home. He often went there after to school to spend evening hours there.

Investigators are trying to figure out how the kids got ahold of the gun.

Stay with ClickOnDetroit.com for more information as it becomes available.