CHESTER, Ill. (AP) — A union official says numerous inmates were involved in an assault that injured two guards and a chaplain at Menard Correctional Center in southwest Illinois.

Kevin Hirsch is president of Local 1175 of the American Federal of State, County and Municipal Employees and a sergeant at the prison. He says one inmate appeared to lure a guard into the attack Tuesday morning. An assault by more inmates followed and the second guard and chaplain were injured.

Hirsch says 10 to 15 inmates were placed in isolation after the incident.

Illinois Department of Corrections spokeswoman Stacey Solano says the prison in Chester is locked down and the incident is under investigation. She says injured staff members were treated at a local hospital.

Neither Solano nor Hirsch would identify the staff members.

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