Update, 3 p.m.
The inmate who died has been identified as 25-year-old Matthew Cook, according to the California Department of Corrections and Rehabilitation.
Update, 1:45 p.m.
Sierra Vista Regional Medical Center called off the “mass casualty incident” at 1:20 p.m., spokesman Ron Yukelson said.
The hospital uses the term “mass casualty incident” when it has been told to expect three or more trauma patients and need more staff, Yukelson said. As of 1:45 p.m., the hospital had received two trauma patients and four patients with less-serious injuries.
Of the inmates taken to Sierra Vista, one of them died, Yukelson confirmed.
Update, 1:35 p.m.
The prison ended its visiting hours on Sunday, and all visitors were escorted out of the prison after the riot broke out, said Lt. Monica Ayon, a spokeswoman for CMC.
“Visiting occurs on Saturday and Sunday, so we will reassess as we approach next weekend,” she wrote in an email.
Update, 1:20 p.m.
One inmate has been confirmed dead, Ayon said. She also confirmed that the riot involved several stabbings.
A riot involving a “large number” of inmates broke out at California Men’s Colony near San Luis Obispo on Sunday.
According to Sierra Vista Regional Medical Center spokesman Ron Yukelson, the hospital was notified of a “mass casualty incident” about noon.
Lt. Monica Ayon, a spokeswoman for CMC, confirmed that a riot broke out at the prison. She said the riot involved a “large number” of inmates, but added officials did not yet know how many inmates were involved. The riot started in the prison yard at Facility A, according to Ayon, and the cause of the riot is currently unknown.
Sierra Vista was told by CMC to expect three trauma patients and six patients with less-serious injuries, Yukelson said. As of 12:30 p.m., Yukelson confirmed that the hospital had received two trauma patients.
Ayon said that about six inmates had been taken out of the prison by ambulance. She said that none of the injuries are life-threatening but may still be serious.
As of 12:35 p.m., Ayon said officials were still in an active situation and were in the process of identifying inmates and clearing the prison yard. None of the prison staff were injured, and there was no use of deadly force, Ayon said.