More than three dozen migrants have died in a fire at an immigration detention center in northern Mexico near the U.S. border, an official said Tuesday.

Images from the scene showed rows of bodies lying under shimmery silver sheets outside the facility in Ciudad Juarez, across from El Paso, Texas. Ambulances, firefighters and vans from the morgue could also be seen.

Thirty-nine people died and 29 were injured in the fire, which broke out late Monday, according to an official with the National Immigration Institute, who spoke on condition of anonymity because they were not authorized to speak publicly about the case.

Ciudad Juarez is a major crossing point for migrants entering the United States. Its shelters are full of migrants waiting for opportunities to cross or who have requested asylum in the United States and are waiting out the process.

Mexico’s attorney general’s office has launched an inquiry and has investigators at the scene, according to media reports.