FOLSOM, Calif. (CBS13) -- Four officers suffered minor injuries in a sudden attack by a group of inmates in a CSP-Sacramento yard, authorities said.
Three correctional officers and a correctional sergeant were checking inmates from the prison's B Block for weapons before releasing them into a maximum security yard when the attack took place just after noon, according to prison officials.
It is not known how many inmates were involved in the attack. Investigators are reviewing surveillance footage to identify all of the participants.
All four victims were taken to the hospital and treated for minor injuries.
Their identities have not been released.
An earlier draft of this article incorrectly identified the prison as Folsom State Prison instead of California State Prison, Sacramento.
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