At least 51 migrants died after being trapped inside a sweltering tractor-trailer truck abandoned in Texas, authorities said on Tuesday 28th, as two Mexican nationals tied to the unprecedented smuggling tragedy were charged in U.S. federal court.

The bodies of the migrants, 39 men and 12 women, most citizens of Mexico, were found on Monday in an industrial area on the outskirts of San Antonio, Texas, about 160 miles (250 km) north of the U.S.-Mexico border. “At least 27 Mexicans, three Guatemalans and four Hondurans were believed to be among the dead, according to officials from all three countries. There was no immediate information on the nationality of the other victims”, according to Reuters.

The incident marked the greatest loss of life on record from a human trafficking attempt in the United States, according to U.S. Immigration and Customs Enforcement (ICE).

According to publication, “local authorities described finding the rear door to the trailer open with ‘stacks of bodies’ inside, while others were strewn collapsed nearby. Some of the victims were hot to the touch, they said”. Among the survivors, there were sixteen people (12 adults and 4 children) who were transported to local hospitals to treat heat stroke and exhaustion.

Two men were charged with the death of these immigrants, according to criminal complaints filed in the U.S. District Court for the Western District of Texas:

Juan Claudio D'Luna-Mendez and Juan Francisco D'Luna-Bilbao have been charged with "possession of a weapon by an alien illegally in the United States," according to the criminal complaints that were filed Monday, the same day the migrants were found. […] Both men are Mexican nationals residing in the US illegally, the affidavits said, as reported by CNN.

Investigators traced the truck's vehicle registration to a San Antonio address that was under surveillance and arrested the two men separately as each was seen leaving the residences.

Craig Larrabee, special agent in charge of Homeland Security Investigations, told CNN that smuggling organizations are now linked to cartels. “In the past, smuggling organizations were mom and pop. Now they are organized and tied in with the cartels. So you have a criminal organization who has no regard for the safety of the migrants. They are treated like commodities rather than people”.

The discovery came as US federal officials launched what they described as an “unprecedented” operation to disrupt networks smuggling people amid an influx of immigrants across the US-Mexico border.

“President Joe Biden described the discovery as ‘horrifying and heartbreaking’. saying the deaths underscored the need to go after criminal trafficking rings. ‘Exploiting vulnerable individuals for profit is shameful, as is political grandstanding around tragedy, and my administration will continue to do everything possible to stop human smugglers and traffickers from taking advantage of people who are seeking to enter the United States’” […], according to the CNN.

The deaths highlighted the challenge the issue of immigration has posed to the Biden administration, which took office as president pledging to roll back some of the more restrictive immigration policies formulated by his predecessor, Donald Trump. Republicans criticize during the president's border strategy, which has also been a source of disagreements within the Democratic Party.