Ten people were killed and dozens wounded in a prison riot early Saturday in the central state of San Luis Potosi, local officials said.
State police said they had re-established control in an cell block of La Pila prison in the state capital of San Luis Potosi after a fight broke out between prisoners, according to a posting on the security ministry's official social media page.
Authorities were investigating the cause of the riot and it was unclear if inmates belonged to rival drug gangs, whose battles have sparked violence across Mexico.
Deadly riots have repeatedly rocked the country's overcrowded prisons, house inmates from different drug gangs that have been fighting over trafficking routes and local turf.
Killings linked to organized crime fell 14 percent to 4,249 in the first four months of the presidency of Enrique Pena Nieto, who took over in December and vowed to reduce the violence that has marred Latin America's second biggest economy.
Former president Felipe Calderon sent the military out to fight drug cartels during his 2006-2012 term, when nearly 70,000 people died in battles and executions, and up to another 27,000 are missing, according to official data.