At least 38 people were killed during a prison riot in Northern Mexico Sunday Febrary 19th.

Inmates took a guard hostage as clashes broke out early Sunday morning at a prison.

Some prisoners also set mattresses on fire, sending a column of smoke rising above the facility.

It was unclear what caused the clashes, which ocurred in a part of the prison where most inmates were serving time for federal drug trafficking offenses.

Authorities have not yet indicated whether the dead were inmates or employees.

They have also not released details about how many people were injured in the fighting.