Three inmates were taken to a hospital after suffering a medical emergency at Pitchess Detention Center in Castaic Tuesday morning.

The incident was reported around 11:25 a.m. at the facility located at 29320 The Old Road, according to the Los Angeles County Fire Department.

The agency told the Associated Press that of the three hospitalized, one was in critical condition, while two others suffered moderate injuries.

An additional 14 inmates had minor complaints and were treated at the facility.

A preliminary investigation from the L.A. County Sheriff’s Department suggests the inmates may have “ingested a controlled substance,” authorities said without elaborating.

Check back for updates on this developing story.