WASHINGTON (NYTIMES) - United States President Donald Trump and his top immigration officials on Sunday (July 7) contested reports that migrant children were being held in horrific conditions in federal detention facilities, as the administration argued that the government was enforcing oversight standards even as it struggled to house and care for an influx of migrants.

Accounts of disease, hunger and overcrowding have multiplied in recent days, but Kevin K. McAleenan, the acting secretary of homeland security, and Kenneth T. Cuccinelli II, the acting director of US Citizenship and Immigration Services, maintained that the facilities were safe.

Pressed on a report by The New York Times and The El Paso Times in which Border Patrol agents and others who had visited a facility in Clint, Texas, described crying children, cases of chickenpox, scabies and shingles, and inadequate medical care, Mr McAleenan dismissed the details as "unsubstantiated".

"What I can tell you right now is that there's adequate food, water," he said in an interview on ABC's "This Week".

"For over a year, there's been showers there."

Still, he and Mr Cuccinelli acknowledged that the government's resources had been strained by the surge of migrants seeking asylum at the southwestern border.

"It's an extraordinarily challenging situation," Mr McAleenan said. "I'm not denying that there are challenging situations at the border."

Speaking to reporters, Mr Trump called the report about the Clint facility a "hoax".

"The Fake News Media, in particular the Failing @nytimes, is writing phony and exaggerated accounts of the Border Detention Centers," he wrote on Twitter.

The Times said in a statement that it stood by the article. "We are confident in the accuracy of our reporting on the US Border Patrol's detention centers," the statement said.

With Congress set to return on Monday after a weeklong recess for the Fourth of July holiday, lawmakers are preparing to confront the accounts of squalor in the border facilities and reports of current and former Border Patrol agents deriding migrants and making vulgar remarks about Democratic lawmakers in a private Facebook group.

Mr McAleenan and Mr Mark Morgan, the acting commissioner of Customs and Border Protection, have been called to testify this week before the House Oversight and Reform Committee to discuss the concerns.