By Cecilio Padilla

REPRESA (CBS13) — Corrections officials say about 20 inmates were involved in a riot at Folsom State Prison on Thursday morning.

The incident happened just after 9 a.m. in one of the prison’s medium-security housing units while the inmates were in the middle of program activities.

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Correctional officers tried to break up the fight, but it took deploying chemical agents to stop the violence. After the fight, five inmates were taken to a nearby hospital to be treated for non-life-threatening injuries.

No prison staff were hurt in the riot, officials say.

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More from CBS Sacramento:

Exactly what led up to the fight is now under investigation.

Officials say they have limited inmate movement as a result of the fight and to help investigate the incident.

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