A sixth correction officer was arraigned Monday on a second-degree murder charge in connection to the death of inmate Robert Brooks.

Nicholas J. Kieffer, 33, of Whitesboro, appeared in Oneida County Court. He is also facing charges of manslaughter, gang assault and offering a false instrument for filing.

Brooks was beaten inside Marcy Correctional Facility on Dec. 9 and died the next day at a hospital. Body camera footage showed correction officers punching and kicking Brooks and grabbing his collar. Other staff members were seen watching the assault.

Brooks had injuries all over his body, including his head, neck and chest.

Nicholas Anzalone, Anthony Farina, Matthew Galliher, David Kingsley and Christopher Walrath were arraigned Thursday on second-degree murder charges.

Kiefer was not in court on Thursday because of what prosecutors said was a misunderstanding with his attorney.

New York State Police Superintendent Steven James said this arrest is a testament to the dedication and professionalism of their investigators.

“The brutal nature of this crime is deeply disturbing, and the level of violence inflicted upon Robert Brooks was egregious. Our members have worked tirelessly to ensure those responsible are held accountable. We hope this arrest brings some measure of justice to the family and loved ones of Mr. Brooks,” James said in a statement.