SAN LUIS OBISPO (AP) — Authorities say an inmate has been killed and several others were stabbed in a large riot at a prison on California’s central coast.

Corrections officials say the melee involving more than 160 inmates broke out around midday Sunday in the yard at California Men’s Colony near San Luis Obispo.

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A total of nine wounded inmates were taken to an outside hospital for treatment. Officials say one inmate died.

California Men's Colony in San Luis Obispo County (CDCR)

California Men’s Colony in San Luis Obispo County (CDCR)

Lt. Monica Ayon, a spokeswoman for the prison, tells the Fresno Bee that visitors were escorted out when the riot broke out. The incident was contained to the yard, which was cleared after about an hour.

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No guards were hurt.

Officials say they don’t know what sparked the violence.

The CMC is a male-only state prison with about 3,800 inmates 200 miles northwest of Los Angeles.

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