Updated

A Cincinnati-area prosecutor says a 13-year-old boy accused of killing his grandfather somehow caused the man's head to plow straight into a wall like a battering ram, fracturing his neck and leaving behind a hole in the drywall.

The boy is charged as a juvenile with murder in the August death of 80-year-old Fowler Agenbroad. The child was 12 then. He has denied the charges.

An assistant prosecutor described the alleged altercation on Monday in court, where a juvenile court judge ruled the boy competent to face trial. The Cincinnati Enquirer reports that a psychological evaluation is pending.

Records indicate police were called about a violent argument between Agenbroad and his grandson two days before the man was found unresponsive.

The Associated Press generally doesn't identify juveniles charged with crimes.