An attack on prison employees prompted a lockdown at the Menard Correctional Center.

Inmates attacked an officer, a guard and a third person in the prison chapel Tuesday in downstate Chester, about 60 miles south of St. Louis.

Menard is Illinois’ biggest prison; officials there say guards face growing danger because of state-mandated staff cuts caused by the state’s financial problems.

The guards’ union at Menard has been without a contract since last summer.