A man has pleaded guilty to second-degree murder and attempted child abuse in the 2010 death of his girlfriend's young son in Mesa.
Maricopa County prosecutors say 26-year-old Jorge Alberto Busso Jr. changed his plea during a court hearing Tuesday.
He's scheduled to be sentenced on Jan. 21.
Mesa police officers were called to a hospital on Dec. 3, 2010.
Hospital staff reported 4-year-old Ramon Alejandro Haro Colin was being treated for massive head trauma and body bruises.
Police say Busso discovered the child had soiled himself while he was alone. They say Busso told officers that he struck the boy and his head hit a wall. However, the child wasn't taken to a hospital until his mother came home from work.
Police say the child died two days later.