Three inmates are in critical condition and seven others seriously injured after a riot at Kern Valley State Prison.
Just before 10 a.m. Thursday, correctional officers say there was a riot on both sides of the maximum security yard in Facility B.
"There was possibly some pre-planning involved, but at this time it's still really early in the game to speculate on any of that," said Lt. Jeff Smith, Kern Valley State Prison.
Officers say there were 100 to 150 inmates in the yard when about 50 inmates started to fight. Prison staff says they got the riot under control within ten minutes.
"The inmates got down, complied with staff directions after the use of less lethal munitions, which we have 40mm direct impact sponge rounds were used and chemical agents in the form of tear gas and pepper spray," said Smith.
Ten inmates were sent to the hospital with critical and serious stab wounds.
Correctional officers say they did recover several manufactured weapons from the yard and are now processing the evidence and interviewing inmates.
Lt. Smith says no staff members were hurt during the riot.
"It is a testament to our training and our staff that they were able to quell this incident so quickly and so effectively," continued Smith.
The maximum security prison holds nearly 4,000 inmates.
Lt. Smith says the last riot at Kern Valley State Prison was January 2012. It involved 300 inmates.