In a chilling 911 call, a migrant tells dispatchers that he and about 80 other people are trapped in a white tank truck unable to breathe.
"We can't see anything. We're inside a tank truck. God, we have no oxygen," the caller tells the dispatcher in Spanish. A man can also be heard in the background begging in Spanish, "Help! Blessed God!" as he struggles to breathe.
In the background, other people can be heard screaming for help in Spanish and saying that they’re out of air.
The call, which took place on Monday but was obtained by NBC's sister network Telemundo on Thursday, triggered a search for the migrants in Texas. Surveillance images show the tank truck in the San Antonio area.
An official with Immigration and Customs Enforcement (ICE) told NBC News in an email that the agency's Homeland Security Investigations unit, along with local law enforcement partners, is still looking into the "possible human smuggling event."
Authorities are now asking for the public's help in finding the tank truck, where some people may have already died, Telemundo reported.
"I'm only interested in knowing if these people are okay. I'm not interested in arresting the people who were inside the truck," Bexar County Sheriff Javier Salazar, whose jurisdiction includes San Antonio, told Telemundo in Spanish.
The investigation comes as arrests of migrants at the U.S.-Mexico border have been increasing after a steep drop at the start of the coronavirus pandemic. U.S. officials in January encountered nearly 78,000 migrants attempting to cross the southern border illegally or who were denied at ports of entry, a 6 percent increase over the previous month.