A battle between two groups of inmates inside the Topo Chico prison in the northeastern Mexican city of Monterrey has left 52 people dead, and five at risk of dying from their injuries, Nuevo León Governor Jaime Rodríguez has said.
Rodríguez told a press conference on Thursday morning that the violence included inmates setting fire to sleeping quarters and a storage area. He said it broke out around midnight and was over well before dawn, and that one of the factions was headed by a leader of the Zetas drug cartel.
The governor explicitly ruled out earlier reports that the riot was triggered by an attempted escape and stressed that no inmates were missing.
He also called for patience while the authorities identified the victims, which he said would take several hours more.
Television images during the morning showed relatives of inmates desperate for information regarding the identity of the dead and injured, shaking the prison gates and tossing rocks at guards and police on the other side. Some could be heard calling out the names of inmates in the hope of getting a reassuring response.
"I want to know that my daughter is OK. She is in the infirmary. There are children in there," one woman said outside the prison.
"They burned everything," said another woman who said she was inside the jail when the violence started. Covering her face with a hood to hide her identity she added, "There were lots of dead people and people who had burns."
Milenio TV reported that the riot broke out when some relatives were on the premises for conjugal visits. Governor Rodríguez later said that there were no women or children among the dead or injured.
Television images showed police vehicles patrolling the streets near the prison after daybreak. Local media also reported that many prisoners were being transferred to other jails.
The incident is the latest in a series of deadly riots that in recent years have rocked Mexico's chronically overcrowded prisons where the potential for conflict is heightened by the presence of inmates from rival criminal groups, as well as endemic corruption.
In 2013, at least 13 people were killed and 65 injured in a prison riot, which was blamed on gang violence, in the central Mexican state of San Luis Potosi.
In 2012, at least 44 inmates died in a Nuevo León prison when members of the notorious Zetas drug cartel plotted an elaborate escape with prison guards.
Pope Francis is to begin his first visit to Mexico as pontiff on Friday. Next week, he will visit a prison in the border city of Ciudad Juarez, which was once one of the most violent cities in the world.
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