More than 50 people were treated for injuries suffered in the Saturday riot at the California Institution for Men in Chino east of Los Angeles. Guards battled for four hours to quell the fighting, which began at 9:24 a.m. on Saturday, said Oscar Hidalgo, a spokesman for the California Department of Corrections and Rehabilitation.
''They used everything from tear gas, batons, they used wooden and foam projectiles,'' he said of the guards. ''There were so many inmates involved at one time that they had to pull back and regroup.'' It was one of the state's largest such uprisings in years.
''We believe initially two individuals were fighting in the yard which were a black and a Hispanic inmate,'' said Mark Hargrove, a spokesman for the Chino prison. ''Everyone kind of drew their racial lines and began fighting between the races.'' Inmates in California's prisons often join racially based gangs and shun interaction with those from other races.
Officials brought in reinforcements from other prisons and local police, both to regain control of the prison and assure that no one escaped from the area, which covers 2,500 acres (1,012 hectares), during the fighting.
One inmate suffered stab wounds and was in serious condition while 27 other inmates were taken to area hospitals for medical treatment, Hidalgo said. Another 24 were treated for minor injuries at the prison and one guard suffered heat exhaustion.
The Chino prison, which first opened in 1941, is divided into four facilities with minimum to medium security with 200 inmates living in each dormitory area. About 95 percent of the inmates are parole violators who have been returned to custody, spokesman Hargrove said.
The prison was under lock-down yesterday and officials were inspecting the damage, included broken glass in all of the windows in the five units where fighting took place, or about 200 total windows, Hargrove said.
''We're looking at transferring approximately 36 inmates because of unacceptable housing situations,'' Hidalgo said. ''It is one of the largest altercations we've had, no doubt.'' The Chino prison offers a number of educational programs seeking to rehabilitate inmates, and just a few weeks ago the facility invited journalists to view their program to train deep-sea divers.