MARTINEZ (CBS SF) — The Contra Costa County Sheriff’s Office is investigating an in-custody death that occurred Friday afternoon in Martinez.

A deputy found a male inmate unresponsive in his cell in the Martinez Detention Facility around 1:36 p.m., according to sheriff’s office officials.

Deputies and jail staff began CPR and called for an ambulance and paramedics, but the inmate was later declared dead.

The inmate’s identity has not yet been released pending notification of next of kin.

The death is being jointly investigated by the sheriff’s office and the Contra Costa County District Attorney’s Office.

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