WARREN, Pa.—A patient at a state hospital in northwestern Pennsylvania has been jailed on charges that he attacked two staff members with a heavy wooden object.

State troopers from the Warren barracks aren't describing the object they say 31-year-old Darian Johnson, of Hermitage, allegedly used to hit the staff at Warren State Hospital shortly before 1 a.m. Monday.

Police say the staff members were both treated for swelling and bruising. Police did not immediately say what led to the incident, and a call to the Pennsylvania Department of Public Welfare has not been immediately returned.

Online court records don't list an attorney for Johnson who is in the Warren County Jail on charges of aggravated assault, simple assault and reckless endangerment.