Dozens of people are reported to have been killed in a riot and a fire at a prison in northern Mexico.
Some inmates are also said to have escaped from the Topo Chico prison near the city of Monterrey.
Smoke could be seen billowing from the complex, Mexican broadcaster Televisa reported.
Streets outside the jail were blocked by families worried about relatives inside. Riot police were holding the crowd back.
Officials have so far made no comment and it was not immediately clear how many people had died. Televisa put the toll at 30, while Milenio TV said 50 people had been killed.
Milenio said inmates and guards were among the casualties.
Witnesses reported hearing shouts and explosions when the fire began in the early hours of Thursday.
Mexican newspaper El Universal said one of four buildings in the prison had been set alight by inmates burning furniture and rubbish.
The cause of the riot was not clear. One report said it had been triggered by an escape attempt by prisoners belonging to the notorious Zetas drugs cartel.
Gang violence and break-outs are common in Mexico’s notoriously overcrowded and corrupt prison system.
In 2012, 44 inmates were killed in a riot at the Apodaca prison in Monterrey. Another 30 prisoners escaped. The prison’s director was later sacked.