Five inmates at Ironwood State Prison in Blythe have been seriously injured after a fight broke out involving more than 100 inmates.

A spokesman for the California Department of Corrections and Rehabilitation says the fight occurred Saturday afternoon in an outdoor yard. Bill Enfield says prison guards had to fire a warning shot to quell the situation. He also says the five injured inmates were taken to nearby hospitals for treatment.

No immediate information on their conditions, or the circumstances that led to the fight has been released.