President Trump last month tours the U.S. border with Mexico at the Rio Grande on the southern border in McAllen, Tex., where a 45-year-old Mexican national died in government custody on Monday. (Evan Vucci/AP)

A 45-year-old Mexican national detained by U.S. Customs and Border Protection died Monday at a medical facility in McAllen, Tex., after twice seeking medical attention, the agency reported.

The fatality followed the deaths in December of two migrant children in government custody, which prompted a vow from CBP to conduct health checks on all children in its “care and custody,” as the agency’s commissioner, Kevin K. McAleenan, said at the time. The fate of those two children, both from Guatemala, renewed concerns about the “zero-tolerance” immigration policy pursued by President Trump.

Another death is likely to raise fresh questions for the border control organization at the forefront of that policy, especially as the president crusades for a wall at the southern border. Trump’s critics point to a humanitarian crisis fomented by his own hard-line approach, rather than a crisis of illegal entries that he falsely claims is overwhelming the Southwestern United States.

According to a statement Monday from the agency, the unnamed adult was apprehended on Feb. 2 for “illegal reentry,” which means the individual had tried to enter the country at least once before. The migrant came into contact with authorities near a port of entry in Roma, Tex., about 50 miles northwest of McAllen.

The detainee requested medical attention and was transported to a hospital in Mission, Tex., adjacent to McAllen. The same day, the individual was cleared to travel and sent back to a CBP station in Rio Grande City, close to Roma.

On Feb. 3, the detainee again requested medical attention, and, according to CBP, was transported to the McAllen Medical Center “shortly thereafter.” The Mexican national was diagnosed with cirrhosis of the liver and congestive heart failure and remained at the 441-bed hospital from Feb. 3 until dying just before 9 a.m. Monday.

The official cause of death was unknown. The border control agency said its Office of Professional Responsibility was conducting a review. It had also notified the Department of Homeland Security’s inspector general, responsible for oversight of the department, as well as Congress and the Mexican government.

“This loss of life is tragic,” Andrew Meehan, a CBP spokesman, said in the news release. “Our condolences go out to the family and loved ones. CBP remains committed to ensuring the safe and humane treatment of those within the care of our custody.”

As of last month, when NBC News published a review of audits and other government reports, at least 22 immigrants had died in American detention centers over the previous two years.

In the same period, the DHS’s Office of Inspector General issued numerous warnings about improper care at detention centers maintained by Immigration and Customs Enforcement, which receives migrants once they are processed at border facilities. A report released in December 2017 identified “problems that undermine the protection of detainees’ rights, their humane treatment, and the provision of a safe and healthy environment.” Earlier that year, the oversight office found ICE agents were not always recording and promptly reporting instances in which detainees had been separated because of mental health problems.

The December deaths of 7-year-old Jakelin Caal and 8-year-old Felipe Gomez Alonzo came amid record-breaking numbers of families seeking entry to the United States. Holding cells filled up as Trump promised an end to a policy he calls “catch and release.”

Meanwhile, facilities designed for single men proved inadequate for a more diverse population of migrants and asylum seekers, illustrated by a rash of illnesses at the end of last year. Homeland Security Secretary Kirstjen Nielsen said the immigration system had reached a “breaking point,” advising those planning border crossings to desist. But advocates for immigrants warn that new barriers will only shift journeys to more remote and dangerous locations.

The budget compromise reached by lawmakers last week includes $415 million for humanitarian needs at the border, including medical care and transportation. That figure is significantly lower than the $800 million sought by Nielsen.

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