A deadly riot at a prison for illegal immigrants in Mississippi was started by a group of Mexican inmates angry about what they considered poor food and medical care and disrespectful guards, according to an FBI agent's affidavit.

One guard was killed and 20 people were injured in the May 20 riot at the privately-run Adams County Correctional Facility in Natchez, which holds illegal immigrants convicted of crimes in the United States.

The leaders of the Mexican inmates, known as the Paisas, demanded to take a list of grievances to the warden that day and told others in the group to disobey orders from prison staff, according to the FBI affidavit. The affidavit, filed last week in U.S. District Court in Jackson, is part of a complaint charging one of the inmates with rioting.

Correction officer Catlin Carithers was beaten to death during the riot, which officials have said involved as many as 300 inmates and left the prison badly damaged. The affidavit does not say who killed Carithers.

The affidavit says the Paisas were the most influential group in the prison. But it had recently gone through a shake-up in its leadership because members thought the old leaders weren't effective in communicating complaints to prison officials. The new leaders — Ernesto "Neto" Granados and Juan "Bobby" Arredondo — allegedly ordered the Paisas to disobey prison staff by refusing to return to their cells until their demands were met.

FBI spokeswoman Deborah Madden said Paisas are a loosely affiliated group within the prison, without ties to organized gangs.

"The Paisas were further instructed by their new leaders to destroy the prison if staff made any attempts to break up the riot," the affidavit said. It says damages to the prison are estimated at more than $1.3 million. "In addition to destroying the prison, Paisas planned to assault the correction officers."

At one point, the inmates gained access to a section of the prison by telling the warden they wanted to go back to their cells, but they ended up taking more hostages once they got into that part of the facility, the affidavit said. Other inmates were able to break through a fence and get a 32-foot ladder, which they used to get on the roof of a building. That's where Carithers was killed.

The affidavit describes a chaotic scene in which inmates were picking up tear gas canisters and hurling them back at guards. Some guards locked themselves in safe rooms, but the inmates used keys taken from other officers to get into the rooms. They also looted the kitchen and commissary.

The affidavit is part of a criminal complaint that alleges that Juan Lopez-Fuentes was in charge of a group of inmates who took hostages in one section of the prison. Lopez-Fuentes allegedly forced one of the hostages, a prison guard, to relay orders for tactical teams to drop their weapons and back off.

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, officials have said.

The prison holds nearly 2,500 low-security inmates, with most serving time for coming back to the United States after being deported. The facility is owned by Nashville, Tenn.-based Corrections Corporation of America, one of the nation's largest private prison companies.

Attorneys could not be found for Granados and Arredondo. Lopez-Fuentes' attorney did not immediately respond to a request for comment.


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