OKLAHOMA CITY (KFOR) – An Oklahoma County Detention Center inmate was pronounced dead at a hospital on Thursday after he was found unresponsive in his jail cell.

Detention Center officials are not yet releasing the name of the 53-year-old male inmate. Next of kin must be notified first.

A jail staff member went to the inmate’s cell to perform a mental health check at around 9:12 a.m. Thursday, but found the inmate unresponsive, according to a Detention Center news release.

The staff member immediately called for other staff and medical personnel to come to the cell, which the detainee had been alone in, the news release states.

“Medical staff immediately began resuscitation efforts and called for an ambulance. Once on scene, paramedics and fire personnel administered CPR until arrival at the hospital,” the news release states. 

The inmate was declared dead at around 10:25 a.m.

The Detention Center Special Investigations Unit will investigate circumstances leading up to the inmate’s death.

The State Medical Examiner’s Office will officially determine the cause of death.