OKLAHOMA CITY (AP) — Authorities are investigating after an Oklahoma County inmate died while in police custody over the weekend.

The Oklahoma County Sheriff's Office says 53-year-old Ricky Windle was found unconscious in his cell on Saturday. Authorities say detention center employees tried to revive Windle, but he died Sunday at a hospital.

Windle had been jailed for failing to register as a sex offender.

Authorities say Windle was being housed in a cell by himself. The state medical examiner will determine his cause of death.