(KRON) — An Oakland murder suspect suffered a “medical emergency” and died inside a cell at Santa Rita Jail in Dublin, officials said.

Inmate Jeffrey Bryce McMaster, 44, of Oakland, died on Saturday afternoon, the Alameda County Sheriff’s Office said. “Deputies heard a noise coming from the cell. Upon opening the cell door, they observed Mr. McMaster on the floor experiencing a medical emergency,” the sheriff’s office wrote.

McMaster had been in custody since February 3, when he was arrested by the Oakland Police Department and booked into jail. Police said the homicide victim was 47 years old.

The inmate suffered a seizure inside his cell on May 28. “Mr. McMaster was transported by ambulance to a local hospital for further medical treatment. On June 6, 2026, Mr. McMaster was medically discharged and cleared for further incarceration,” the sheriff’s office wrote.

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McMaster was undergoing a medical screening at the jail when he requested to use a restroom, officials said. After deputies escorted him to a nearby cell with a bathroom, the inmate collapsed and died.

His official cause of death will be determined by a forensic pathologist following an autopsy and toxicology testing, the sheriff’s office said.

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