PLYMOUTH (AP) -- Authorities found ammunition in the suburban Minneapolis home of a 7-year-old boy who fatally shot himself with a loaded handgun found in a box containing a toy.

A search warrant says a half-full box of ammunition was found in a diaper bag in the Plymouth residence where Keyaris Samuels died May 16.

The boy's mother told police she didn't know anything about a gun in the house, and that a friend visited earlier that day and must have left it there. That friend is in custody after missing a parole meeting.

No one is charged in the boy's death.

The ammunition found by police would have fit the handgun. Testing showed multiple people handled the gun the day Keyaris died, and officials requested DNA from the mother's friend.