WASHINGTON (AP) — An inmate was killed Thursday after being beaten inside a high-security federal prison in Illinois. That’s according to two people familiar with the matter who spoke to The Associated Press on Friday.

The Thursday death at the prison known as USP Thomson is the latest serious security issue for the federal Bureau of Prisons, which has been plagued by chronic violence, serious misconduct and persistent staffing shortages.

It once again raises questions about whether officials at the embattled Justice Department agency can adequately protect the safety of the more than 170,000 federal inmates across the U.S.