An inmate who had been imprisoned for 50 years and participated in a notorious 1971 escape attempt from San Quentin was killed and numerous others injured in a riot on Wednesday afternoon at a prison outside Sacramento, officials said.
Eleven inmates were taken to hospitals with stab wounds and "numerous" others were injured during the incident at California State Prison-Sacramento just before 1 p.m., the California Department of Corrections and Rehabilitation said in a statement.
The corrections department said inmate-made weapons were used in the stabbing melee, which involved 70 prisoners and was described by officials as a riot.
No staff members were injured in the disturbance, which occurred in a maximum-security general population yard, the state said.
Officials identified the inmate killed as Hugo Pinell, 71, who had been in custody since 1965. Pinell, who was originally convicted of rape and sentenced to life with the possibility of parole, was later convicted in the March 1971 murder of a prison guard.
Later that year, he and others known as the San Quentin Six participated in an escape attempt from the state's San Quentin prison near San Francisco in which six people were killed.
He was convicted of assaulting two prison guards in the escape attempt on Aug. 21, 1971.
Two prison guards and four inmates, including George Jackson, a founder of the Black Guerrilla Family prison gang, died in the San Quentin incident, the state said.
Corrections officials said prisoners' movements would be limited as the investigation into Wednesday's disturbance unfolded.
The Sacramento prison has been the site of several violent outbreaks in recent years.
In September 2012, an inmate was shot by a guard and 12 others were sent to the hospital with stab wounds and head trauma in a melee involving 60 inmates.
About a year earlier, nine inmates were taken to a hospital with stab and gunshot wounds as well as blunt force trauma after 50 inmates rioted.
The prison is a maximum-security facility that houses about 2,300 inmates, most serving long sentences.
Also known as "New Folsom," it is adjacent to Folsom State Prison, which is better known because of the song "Folsom Prison Blues" by Johnny Cash, who also performed a celebrated concert there in 1968.
(Reporting by Sharon Bernstein in Sacramento, Calif. and Curtis Skinner in San Francisco; Editing by Peter Cooney)