Officials say an Ohio inmate who intentionally overdosed on pills hours before his scheduled execution has returned to prison and is on suicide watch.

Prisons spokeswoman Julie Walburn says 43-year-old Lawrence Reynolds Jr., who admitted taking an overdose of medication prescribed to him, arrived at the Ohio State Penitentiary in Youngstown shortly after noon on Tuesday.

Walburn says Reynolds is isolated from other inmates and under constant observation.

Reynolds was treated at a Youngstown hospital after he was found unconscious in his death row cell Sunday night.

The type of drug he used and why it was prescribed aren't being disclosed. How he accumulated the pills is under investigation.

Reynolds' execution for the 1994 murder of his neighbor near Akron has been rescheduled to next week.