CIUDAD VICTORIA, Mexico (AFP) — A fire started by inmates at a prison in northern Mexico left at least three prisoners dead and one person injured, officials said Saturday, just days after 29 detainees escaped through a tunnel.

“Three dead and one seriously injured in a dispute between inmates. Prison under control measures,” the security spokesman for Tamaulipas state said on Twitter. 

The large blaze broke out Friday night at the prison in the state capital of Ciudad Victoria after inmates staged a protest, starting several fires.

Tamaulipas, which lies below the southernmost tip of the US state of Texas, is a hotbed of organized crime because of its strategic location on drug trafficking routes to the north.

The Mexican state is the scene of a bloody turf war between the Zetas and Gulf drug cartels.

The facility in Ciudad Victoria is among the most troubled in Mexico. Inmates control large parts of the prison and practice a sort of “self-government,” even setting up shops in one area.

On Wednesday, at least 29 inmates fled the prison through a tunnel 40 meters (130 feet) long and five meters (16 feet) deep.

Twelve were recaptured on Thursday and another on Saturday, but the rest remain at large. The inmates killed one person while stealing a getaway car.

The tunnel was located in the prison’s illegal commercial zone, which was dismantled by police after the tunnel escape. In response, prisoners fired guns and burned sheets.

The unrest raged on Friday, with the fire burning until midnight.

Many Mexican prisons suffer from underfunding and overpopulation, leading to riots and escapes as authorities struggle for control.