LOS ANGELES , California ( CNN ) -- More than 250 inmates were injured in a riot that erupted overnight at the California Institution for Men in Chino , a spokesman said Sunday . Flames leap from a housing unit at a prison in Chino , California , on Saturday night . Fifty-five inmates were taken to area hospitals with serious injuries , said Lt. Mark Hargrove , prison spokesman . None of the facility 's employees was hurt in the melee , which broke out at about 8:20 p.m. Saturday at the Reception Center West facility , Hargrove said . Guards used pepper spray , `` less lethal force , and lethal force options '' to regain control by 7 a.m. Sunday , he said . The scene of the violence was the medium-security housing facility with seven units , each of which houses about 200 inmates , he said . Some 80 officers responded to the riot , during which a housing unit was heavily damaged by fire , he said . The institution was placed on lockdown pending an investigation into the cause of the fighting , and visiting privileges were suspended . Hargrove said several other prisons in southern California were placed on lockdown as a result of the riot at the Chino facility and the possible need of reallocating prison staff to Chino . Aref Fakhoury , acting warden for the California Institution for Men , said police departments from the cities of Chino , Chino Hills and Ontario , and the Chino Valley Independent Fire District aided in quelling the violence . The inmates ' injuries ranged from stab wounds and slashes to head trauma , Hargrove said . Some were considered life-threatening . Hargrove said inmates used `` weapons of opportunity , '' such as broken glass during the riot . Images taken from the scene showed flames coming from the building as a helicopter hovered overhead . A similar riot broke out in December of 2006 , Hargrove said . Chino is located about 35 miles east of Los Angeles . CNN 's Jackie Castillo contributed to this report .
No employees at California Institution for Men in Chino were injured . Order restored by 7 a.m. but prison on lockdown pending probe . Fifty-five inmates treated at hospital after melee . Lt. Mark Hargrove , prison spokesman : Inmates have stab wounds , head trauma .