Four Officers with the St. Louis Police Department have been indicted by a federal grand jury and may face federal charges of civil rights violation, obstruction of justice and lying to federal investigators.

Officers Dustin Boone, Bailey Colletta, Randy Hays, and Christopher Myers are accused of beating a demonstrator during protests last year and trying to cover up the assault.

That demonstrator who came under assault during the incident turned out to be a 22-year veteran of the police department who was working undercover, according to KTVI-TV News.

The four officers are scheduled to appear in court on Thursday. They are presently on administrative leave without pay.