Three Illinois prison guards were arrested this week on federal obstruction and civil rights charges in connection with the death of an inmate who was fatally beaten last year, the authorities said.

Lt. Todd Sheffler, 51; Sgt. Willie Hedden, 41; and Officer Alex Banta, 28, were arraigned in federal court in Springfield, Ill., on Friday afternoon for their roles in the May 17, 2018, assault of Larry Earvin at the Western Illinois Correctional Center in Mount Sterling, according to the United States Attorney’s Office for Central Illinois.

Mr. Earvin, 65, who sustained multiple broken ribs, a punctured colon and other serious internal injuries in the attack, died six weeks later from blunt trauma injuries. His death was ruled a homicide, according to The Associated Press, which obtained a copy of the autopsy report last year.

The assault on Mr. Earvin occurred as Lieutenant Sheffler, Sergeant Hedden and Officer Banta moved him from his residential unit to the Mount Sterling prison’s segregation unit, according to the grand jury’s indictment, which was obtained by The Associated Press.