ST. LOUIS (AP) — Four detainees at a downtown St. Louis jail were injured when they were stabbed during a fight — the latest of several instances of violence at the jail.

A guard sent out a distress call about a disturbance around 1:20 p.m. Wednesday at the City Justice Center, spokesman for the St. Louis Department of Public Safety, Monte Chambers, told the St. Louis Post-Dispatch. The injured detainees were taken to a hospital. Their conditions were not immediately made available.

Jail officials are investigating what caused the fight.

The jail has struggled to hire enough guards. Officials said earlier this year that fewer than 100 correctional officers were on staff, though the budget calls for 226 positions.

Advocates for detainees have long complained about conditions at the jail. It was the site of three uprisings between late 2020 and early 2021.

In February 2021, detainees set fires, caused flooding, broke out fourth-floor windows and tossed chairs and other items through the broken glass. A guard also was attacked.

Detainees again broke windows and set a fire during another riot in April 2021. A month later, Dale Glass, the embattled director of the jail, resigned.

And in 2023, detainees abducted a 70-year-old guard for several hours before a police SWAT team intervened. The guard suffered minor injuries.