ST. LOUIS (AP) — A St. Louis police officer has admitted attacking an undercover colleague who he believed was a protester.

Randy Hays pleaded guilty Friday in federal court. A sentencing date has not been set. Hays is no longer with the department.

Hays was one of four officers charged in the crime. Undercover Officer Luther Hall claimed he was beaten "like Rodney King" when fellow officers mistook him for a protester in 2017. The attack happened during a demonstration following the acquittal of Jason Stockley, a former St. Louis officer who had been accused of fatally shooting a black suspect.

The officers were indicted in late 2018. Bailey Colletta pleaded guilty in September to lying to cover up the attack. Dustin Boone and Christopher Myers face trial Dec. 2.

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