Hugo Pinell, 71, was once one of the country's most infamous prisoners. The convicted rapist was one of the "San Quentin Six" whose escape attempt ended the lives of six people, including two corrections officers, three inmates and George Jackson, founder of the Black Guerilla Family prison gang, a corrections spokeswoman said.
A fellow inmate attacked Pinell on Wednesday in the exercise yard, sparking a behind-bars battle.
The violence broke out around 1 p.m. local time in a maximum security general population yard of the state prison, authorities said.
"Inmate-made weapons were used" during the brawl, authorities said.
Long live the spirit of Yogi (Hugo Pinell), long live George Jackson, BGF!
Bottom row, left to right: Johnny Spain, David Johnson, Willie Tate; top row, left to right: Fleeta Drumgo, Luis Talamantez and Hugo Pinell
During the escape, which sparked a riot on the cellblock, Jackson had a .32 caliber pistol allegedly smuggled into the prison by attorney Stephen Bingham (immediately after the incident, Bingham went on the run and fled the country for 13 years; he returned in 1984 to stand trial, and was acquitted of all charges in 1986). During the riot caused by Jackson and two dozen other prisoners, three corrections officers and two inmates were tortured and killed.
In addition to Jackson, those killed in the altercation were guards Paul E. Krasenes, 52, Frank DeLeon, 44, and Jere P. Graham, 39, as well as inmates John Lynn, 29, and Ronald L. Kane, 28. Spain was found guilty in the shooting deaths of guards DeLeon and Graham, Pinell was convicted of cutting the throats of guards Charles Breckenridge and Urbano Rubiaco, Jr., and Johnson was convicted of assaulting Breckenridge. There were no convictions for the killings of Krasenes, Lynn, or Kane. Cleared of all charges, Drumgo, Talamantaz, and Tate were found not guilty on various counts of murder, conspiracy, and assault.