Oklahoma County Detention Center CID investigating inmate death

The Oklahoma County Detention Center Criminal Investigation Division (CID) is investigating an inmate death that occurred Monday evening.

Jail officials say that in the evening, during a welfare check, a detention officer found Mario Mason, 26, unresponsive in his cell. They say the officer called for medical personnel, and they initiated life-saving measures before he was transported by EMSA to the hospital.

OCDC says that Mason was pronounced dead by the hospital an hour later.

The jail says that Mason has been detained at the jail since May 23, 2024. He was sentenced to life in prison on April 24, 2025, and was awaiting transfer to the Oklahoma Department of Corrections.

The circumstances around his death are under investigation. All deaths at the jail are investigated as homicides until a final determination is made by the State Medical Examiner's Office.

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