(AP) — Preliminary autopsy results confirm the Cleveland man convicted of holding three women captive at his home for about a decade hanged himself in prison.

Officials say 53-year-old Ariel Castro was found hanging in his cell around 9:20 p.m. Tuesday at the Correctional Reception Center in Orient, in central Ohio. Prison medical staff performed CPR before Castro was taken to a hospital, where he was pronounced dead.

The Franklin County coroner says an autopsy done early Wednesday showed it was a suicide, and the cause of death was hanging. She said toxicology tests still would be completed in the coming weeks.

A prisons spokeswoman says Castro was in protective custody because of the notoriety of his case, meaning he was checked every 30 minutes. But he was not on suicide watch.