Massive brawl at San Mateo Co. jail that left 10 injured under investigation, sheriff says

REDWOOD CITY, Calif. (KGO) -- Six San Mateo County jail inmates were hospitalized and four sheriff's office personnel suffered minor injuries in a fight involving about 30 prisoners Friday morning, the sheriff's office said.

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The incident began about 10:45 a.m. during a recreational period in a housing unit at the Maguire Correctional Facility in Redwood City, the sheriff's office said in a press release. The cause of the fight was under investigation.

All six prisoners who were taken to area hospitals were reported to be in stable condition Friday afternoon, the sheriff's office said.

The San Mateo County Deputy Sheriff's Association, which characterized the fighting as "a large riot," said three of its union members were hurt, and one correctional officer was taken to a hospital for treatment.

The union representing sheriff's office sergeants said it "sounded the alarm weeks ago that chronic understaffing" was "unsafe for both the inmate population and sheriff's office staff."

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The jail was immediately locked down and additional personnel responded with "less-lethal" weapons "to swiftly and safely get the situation under control," the sheriff's office said.

Sheriff Christina Corpus praised correctional personnel whose "actions undoubtedly prevented more serious injuries and ensured the situation was quickly under control."

An investigation is underway. Its conclusions will be forwarded to the San Mateo County District Attorney's Office for review, the Sheriff's Office said.

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