Bleak scenes of tearful, malnourished children reeking of filth and jammed into frigid, overcrowded quarters have emerged in new accounts from immigrant rights lawyers, who conducted dozens of interviews with children inside Border Patrol stations across Texas.

The descriptions contained in sworn declarations as part of a legal case stand in stark contrast to what was seen when federal officials opened the doors of a Border Patrol facility outside El Paso on Wednesday.

At the station in Clint, Texas, journalists, including a reporter from NPR, surveyed an orderly and clean facility in which pantries were stocked with snacks like microwavable burritos and soup and storage rooms were full of basic supplies like toothbrushes, soap and clothes.

Federal officials who took reporters on the tour said the children have access to showers and other basic necessities.

Reporters were walked past holding cells, but officials did not allow them to talk to the children.

The tour was a rebuttal to accounts provided by lawyers who advocate for migrant children, who recently wrote in legal papers that the conditions in migrant detention centers are so appalling, and in some instances allegedly life-threatening, that it should be considered "a public health emergency."

Immigrant rights lawyers, just hours after the tour, petitioned a federal judge to order additional oversight of Border Patrol holding facilities across Texas, where migrant children are being held.

The filing asked the court to require immediate inspections of the facilities by public health experts and accused the federal government of violating standards for detained migrant care established in a court settlement. The advocates also sought to have detained children released to parents or other relatives living in the U.S.

Lawyers for the Justice Department fought back, telling the court that the request by immigrant advocates for the requirements to take hold immediately should be denied.

"The court should decline to reach any conclusions as to plaintiffs' allegations without affording the government a full and fair opportunity to reply to the allegations that plaintiffs have lodged against them," wrote Sarah Fabian, a lawyer with the Justice Department.

It is the latest chapter in a scandal over the detention of migrant children that has already sparked national outrage.

On Wednesday, lawyers supported their legal filing by providing the court with scores of descriptions of interactions attorneys have had with migrant children in Border Patrol sites, including sworn statements about conversations with minors at the Clint station.

"Toothbrushes are not provided. Few are allowed to shower," one attorney wrote. "Toilets are extremely dirty and sinks contained within lack of running water, soap or towels."

Another lawyer wrote: "Most children are wearing filthy clothing and have not been bathed or been provided clean clothing."

In one instance, a Border Patrol officer used a lollipop to coax a crying six-year-old boy back into his cell. "He wept almost inconsolably for most of the time," attorneys stated.

One lawyer, who interviewed 15 children detained at the Clint station last week, depicted similarly squalid conditions, according to the legal filing.

"Never before in my life have I witnessed, heard of, or smelled such degradation and inhumane treatment of children in federal immigration custody."

A pregnant 17-year-old had been detained with her two-year-old son for 20 days, attorneys wrote. She had not received any prenatal care, and the mother was also stricken with the flu, which can be more serious for pregnant women than for other women, according to the Centers for Disease Control and Prevention.

"Border Patrol guards have made both pregnant mother and toddler sleep on the cold floor without a mattress or blanket," according to the filings.

Another teenage migrant mother, who was confined to a wheelchair and was in pain after having given birth to a premature baby in an emergency procedure, allegedly asked U.S. officials for something she can use to cover her infant.

"She begged her Border Patrol guard for something to wrap the baby in, and she was given a dirty towel," lawyers wrote.

Meals provided to children were bland and not nutritious, migrant children told the legal team.

"Multiple of the children we interviewed described the same three meals a day. Essentially, it was instant oatmeal, a cookie, and a pouch of Kool Aid for breakfast; instant soup, a cookie, and another pouch of Kool Aid for lunch," according to the legal filing.

On Wednesday, however, at least at the Clint site, conditions seemed to have gotten more civilized, with none of the signs of suffering and desperation captured by the interviews submitted to the court by immigrant rights advocates.

Moreover, the number of migrants at the facility had been greatly reduced to around 100 from the more than 300 migrants housed there last week, according to the immigrant rights lawyers who visited the station.

Clara Long, a lawyer with Human Rights Watch who was part of the legal team that visited the Clint site last week, was skeptical that the tour led by Border Patrol was offering an accurate snapshot of what life is like inside migrant facilities.

"You're going to a facility that has been prepared for a tour. They've also moved out hundreds of children from the facility before you visited," Long said. "And they didn't give you access to children, so they could tell you directly what they'd been through in detention."

As migrants continue to stream across the southern border in record numbers, Border Patrol has struggled trying to find enough facilities to house them.

And U.S. migrant housing capacity is being strained, resulting in sites like the one in Clint ending up warehousing hundreds of child migrants for days or weeks, even though legal guidelines dictate that children are supposed to be turned over to the Office of Refugee Resettlement no longer than 72 hours after their detention starts.

"The U.S. government is ultimately responsible here for keeping thousands of unaccompanied children in these jail-like conditions," said Long, the migrant lawyer. "What they need to be doing is making prompt and continuous efforts to release and re-unify these kids."

A spokesman for Customs and Border Protection said it is agency policy not to comment on pending litigation.

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