The boy was alone in the room at the time of the shooting, Arnold said. The boy's two older sisters both younger than 10 were in the home, along with their mom and grandfather at the time of the shooting. The grandmother was not home.
The family heard the gunshot and found the child in the room wounded. They performed CPR on the boy until emergency responders arrived.
The boy was flown by medical helicopter to Primary Children's Medical Center in critical condition and still had vital signs, but died about 8:15 p.m., Arnold said.
Shortly before the shooting, the boy's father had left to catch a plane to Colorado. Authorities were able to track him down before he boarded the plane and took him to the hospital.
Police would not release details on how the child got hold of the gun and where the gun had been stored.
Arnold said it was obvious the gun was not locked up since the child was able to access it. He urged gun owners to secure their guns, especially if children are in the home.
"Little kids don't know a gun from a toy," Arnold said.
Police were not releasing the name of the child Tuesday night.
The Tribune will have more details when they become available.