About 41 inmates rioted Thursday morning at Pleasant Valley State Prison in Coalinga, according to a California Department of Corrections and Rehabilitation news release.
The incident started around 9:40 a.m., when three inmates attacked a fourth, according to the release.
The attack morphed into a riot, which continued to escalate even after correctional officers deployed chemical agents. It ended after an officer fired a warning shot from a Ruger Mini-14 rifle, according to the release.
Three inmates were sent to outside hospitals for treatment of puncture wounds, and no correctional officers were injured, according to the release. Two inmate-made weapons were recovered.
The riot’s cause and the use of deadly force at the 3,300-inmate prison are both being investigated, the release states.