At least 40 people at an immigration detention center in a Mexican city on the U.S. border died in a fire that broke out at the facility overnight, according to a statement issued early Tuesday by the center, known as the National Immigration Institute (INM). Video from the scene in Ciudad Juárez showed bodies covered in blankets lined up in a row outside the facility. 

The INM's statement, shared on Twitter, said 29 other people were seriously injured in the blaze and taken to local hospitals. 

There was no immediate information on what caused the fire to break out around 10 p.m. local time on Monday night, but Mexican media said the country's attorney general had initiated a formal investigation, and that investigators were already on the scene.

The INM statement said 68 adult men were housed at the facility from Central and South America, and that it was communicating with consular officials from various nations to identify the victims of the blaze. 

In a Twitter post, the office of Mexico's attorney general identified the nationalities of the victims: 1 Colombian,1 Ecuadorean, 12 Salvadorans, 28 Guatemalans, 13 Hondurans and 12 Venezuelans.

The Guatemalan Institute of Migration, a government-run entity, said in a statement that it would work with the families to have the remains returned.

"Irregular migration carries with it a series of risks, which have once again become evident; once again we call on the population to analyze and make the right decisions before embarking on such journeys, which often have no return or final destination," the institute said.  

Dozens of ambulances and fire crews responded to the overnight blaze in Ciudad Juarez.

A Customs and Border Protection spokesperson tells CBS News that U.S. border officials are prepared to "quickly process and admit" victims of the fire so they can receive medical treatment in the U.S.

CBP is planning to grant parole to migrant victims of the fire on humanitarian grounds so they can enter the country legally to receive emergency medical services, the agency said in a statement.

Ciudad Juárez, which neighbors El Paso, Texas, is one of the border towns where numerous undocumented migrants seeking refuge in the United States remain stranded.

A recent report by the International Organization for Migration (IOM) states that since 2014, some 7,661 migrants have died or disappeared en route to the U.S. while 988 perished in accidents or while traveling in subhuman conditions.  

The Associated Press contributed reporting.

In:
• Immigration
• Mexico
• Death
• U.S.-Mexico Border
• Fire