JACKSON (AP) — A federal judge has rescheduled the sentencing hearings for two men convicted of participating in a prison riot in Mississippi last year in which one guard was killed and 20 people were injured.

Marco Perez-Serrano, also known as Jesus Fernando Ochoa, and Yoany Oriel Serrano-Bejarano had both been scheduled for sentencing Tuesday in U.S. District Court in Natchez. Their hearings are now set for Feb. 25. The court website did not indicate a reason for the change.

Both men have pleaded guilty to rioting. Their attorneys did not immediately respond to phone messages left at their offices Saturday.

Investigators say Perez-Serrano was the first inmate to attack correction officer Catlin Carithers, who was fatally beaten during the riot at the privately run Adams County Correctional Facility in Natchez on May 20, 2012.

Perez-Serrano hit Carithers with a food tray, and after other inmates joined in the attack, Perez-Serrano was seen hitting another guard with the tray, according to court records.

Authorities say prisoners took food service carts out of the dining hall and kitchen and stacked them on top of each other to climb onto the roof where Carithers was beaten. Serrano-Bejarano was identified in court records as one of the inmates who held the food carts for the other prisoners.

The prison held nearly 2,500 inmates, most of them convicted on charges of returning to the U.S. after deportation for being in the country illegally.

The prison is owned by Nashville, Tenn.-based Corrections Corporation of America, one of the nation’s largest private prison companies.

It took hours for authorities to control the riot, which involved hundreds of inmates and caused an estimated $1.3 million in damage, court records say.

The prison’s special response team and the Mississippi Highway Patrol’s SWAT team worked to end the riot while state and area law enforcement officers, some from neighboring Louisiana, helped secure the outside.