NATCHEZ — An inmate charged in the May 20 prison riot at Adams County Correctional Facility pleaded “not guilty” Friday to the charges against him.

Yoany Oriel Serrano-Bejarano entered the plea before federal Magistrate Judge F. Keith Ball in Jackson, and Friday the judge appointed a public defender for Serrano-Bejarano and set a jury trial for the matter for Dec. 3.

The defendant was indicted Oct. 3 on charges of instigating, conniving, attempting to cause, assisting and conspiring to cause a mutiny and riot.

During the seven-hour riot in which Serrano-Bejarano is accused of participating, a guard — Catlin Carithers, 24 — was killed, and other guards were injured and taken hostage.

Previous court filings against Serrano-Bejarano allege he helped inmates access the roof of a building where correctional officers trying to control the riot were. Carithers was on one of the prison’s roofs when he was assaulted and received the wounds from which he died.

An affidavit filed in September alleges the defendant was one of a number of inmates who stacked food carts in order to reach the officers on the roof.

The affidavit likewise states a participant in the riot told investigators he had witnessed Serrano-Bejarano assaulting a hostage correctional officer during the prison uprising.

The riot started after prison officials tried to contain a mass disobedience by a group of prisoners known as Paisas — an informal prison group composed of Mexican nationals — who wanted to express displeasure with the facility’s operations and staff.

Another inmate accused in the riot, Juan Lopez-Fuentes, pleaded guilty to charges against him Aug. 27, and will be sentenced Nov. 19.