Mexico's National Commission of Human Rights (CNDH) has opened a case into the riot at the Topo Chico prison in Monterrey in which 52 people died and 12 others were injured, the CNDH announced Thursday.
The CNDH condemned the violence and demanded the authorities fully clarify the facts while applying the full extent of the law to those responsible for this tragedy.
If these instructions are not followed, the CNDH warned that the Topo Chico riot could provide a very poor precedent for human rights abuses in Mexico.
The institution also demanded the application of precautionary measures, such as full medical care for the wounded, extensive help for the relatives of the victims, including medical and psychological care, legal advice to the families, and a full inspection to ensure prisons are not overcrowded and remain safe.
The CNDH said it has dispatched a team to gain first-hand knowledge about the health status of the wounded, to gather testimonies, official documents and clues that could lead to the discovery of the complete truth behind the riot.
The intervention of the CNDH is due to the severity of the incident and petitions by the families of the prisoners.
At a press conference in the state capital of Monterrey, Nuevo Leon State Governor Jamie Rodriguez Calderon said the riot erupted between two criminal gangs in the blocks C2 and C3 of the prison complex.
The riot left 52 people dead and 12 others injured, five in critical condition.
A fire broke out inside the prison's storage facility, the governor said, refuting earlier reports that the blaze was set in the prison's area for women and children.
Gangs led by Ivan Hernandez Cantu, alias "El Comandante Credo", and Juan Pedro Salvador Zaldivar, alias "El Z 27", clashed and turned it into a riot. Cantu is a leader of the Gulf Cartel while Zaldivar is a member of the Zetas Cartel.
The violence broke out in the early hours Thursday morning, when a large number of prisoners took over parts of the facility, provoking a large-scale response from the police.
According to Milenio TV, prisoners used furniture and garbage to set one of the prison's four buildings ablaze, a move likely to be done as a cover to help a group of prisoners escape.
No one has escaped the prison, the governor noted, while admitting that conditions in prisons across Mexico were often beyond the control of authorities.
"We are living a tragedy regarding the conditions being found in prisons and penal centers," he said.
Some families of prisoners rushed to the scene for more information, but police had cordoned off nearby streets. A crowd gathered outside, demanding updates on their loved ones.
"We only want information. We have been here since midnight, we have been asking to speak to the mayor or to anyone who can tell us what happened. We know many people have died, that many have been injured but they tell us nothing," a spokesperson for the families told local media.
"We saw the smoke, we saw the fire, we heard the gunshots and the screaming," he said.
At the press conference, Calderon stated that none of the bodies had yet been identified but that work is still unfolding.