Mexican authorities have detained employees of the old and overcrowded Topo Chico prison in Monterrey, following the 11 February riot which resulted in the deaths of 52 people. Roberto Flores, the state prosecutor in Nuevo Leon has since accused prison director Gregoria Salazar, prison guard Jose Reyes Hernandez and the deputy superintendent Jesus Fernando Dominguez of homicide and abuse of authority and has placed them preventive custody.

The riot happened after fighting broke out between supporters of Zeta 27 gang leader, Juan Pedro Saldivar-Farías , who have effectively taken control of the prison, and Jorge Iván Hernández, "El Credo", a leader of another group, Gulf Cartel. It was not immediately clear how the victims died with reports stating that there was no gunfire.

The prison has long housed members of Zeta 27, who have spread fear across Mexico before being debilitated by arrests and the deaths of their founding members. The gang was also linked to another prison murder in Nuevo Leon in 2012, when 44 inmates died after Zeta members plotted with guards to stage an elaborate escape.

Reuters photographer Daniel Becarril visited Topo Chico prison a week after the incident, witnessing the aftermath of what has been described as the deadliest riot in Mexico's history.

Topo Chico
Family members visit inmates in the Topo Chico prison during a media tour in Monterrey, Mexico Daniel Becerril/ Reuters