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Unaccompanied migrant children housed at a U.S. government tent camp inside the Fort Bliss Army base in Texas faced filthy conditions and lacked access to adequate mental health services, according to a whistleblower complaint submitted to Congress and government watchdogs on Wednesday.

Two civil servants in the federal government who volunteered to work at the tent site said distraught migrant children, including some with suicidal thoughts, were referred to staff who were not qualified to assess their trauma and mental health needs. In some cases, children’s requests to speak to a counselor were denied or dismissed, the federal volunteers said.

Arthur Pearlstein, a director at the Federal Mediation and Conciliation Service and one of the whistleblowers, interviewed dozens of children held at Fort Bliss who had symptoms of depression, including concerns about self-harm.

“Many, if not most, of the children Mr. Pearlstein interviewed — if they had been at the facility more than a few days — told him they felt like they were in prison and often begged ‘please get me out of here, I don’t know if I can take it anymore,'” the complaint said. “In some cases, children tried to escape the facility.”

Overcrowding inside large “airplane hangar-sized” tents housing hundreds of migrant teenagers led to the accumulation of waste and dirty clothes, according to the complaint. The volunteers also reported weeks-long shortages of underwear for the boys housed inside the facility. 

A photo provided by a source shows cots inside the tent camp holding migrant children at Fort Bliss.

Obtained by CBS News

The Government Accountability Project, a nonprofit based in Washington, D.C., filed the whistleblower complaint on behalf of Pearlstein and Lauren Reinhold, an attorney at the Social Security Administration. It was shared with four congressional committees, the Office of Special Counsel and the Office of Inspector General at the Department of Health and Human Services (HHS), which oversees the tent camp.

“I am speaking out in the interest of accountability and with the hope that the many avoidable failures in the program at Fort Bliss will not be repeated,” Pearlstein said in a statement. “Gross mismanagement, waste, and abuse of authority by those at the top who insisted on utmost secrecy led to conditions for thousands of children at Fort Bliss that can only be described as constituting mistreatment.”

The complaint, the second one the Government Accountability Project has filed on behalf of federal employees who worked at Fort Bliss, substantiates previous reporting by CBS News that revealed that distressed children housed at the tent camp were constantly monitored for escape attempts, self-harm and panic attacks.

Out of concern that children could harm themselves, officials at Fort Bliss banned pencils, nail clippers and even regular toothbrushes. Wednesday’s complaint confirmed that “riots” broke out in tents housing boys.

The complaint also corroborates CBS News reporting on prolonged stays endured by migrant children. The federal volunteers reported speaking to dozens of teenagers who had been held at Fort Bliss for longer than 30 days and, in some cases, beyond 60 days. 

Unaccompanied migrant children in the care of HHS, which receives them from Border Patrol agents, are supposed to be placed with family members in the U.S. while they continue their court proceedings and requests for asylum or other forms of humanitarian relief.

In response to concerns raised about Fort Bliss, HHS last month said it had expanded mental health services, case management and recreational activities at the Army installation. The department also touted that the number of children at Fort Bliss had decreased to 790, a 82% drop from mid-May, when the site was holding 4,500 teenage boys and girls.

On Tuesday, the tents inside Fort Bliss were housing 1,692 children, including 1,145 boys and 547 girls, according to government data obtained by CBS News.

In the spring, HHS set up enough tents and cots to hold up to 10,000 minors at Fort Bliss. According to recent government documents obtained by CBS News, the site’s maximum capacity is now 4,000, which continues to make it the largest U.S. holding facility for migrant children.

The tent city inside Fort Bliss is one more than a dozen “emergency intake sites” HHS set up this spring to get migrant youth out of ill-suited Border Patrol holding facilities. HHS has since closed most sites, except for Fort Bliss and two other facilities.

A photo provided by a source shows migrant children walking outside tents inside a camp at Fort Bliss, Texas.

Obtained by CBS News

Unlike traditional HHS shelters, the emergency intake sites are not licensed to house children and have lower standards of care and services. As of earlier this week, HHS was housing 13,600 migrant minors, including 3,800 at the emergency sites, according to government documents.

In addition to the federal volunteers represented by the Government Accountability Project, CBS News has spoken to five other government employees who expressed concern about their time at Fort Bliss. In May, there were 800 federal volunteers there, but many have been demobilized.

One of the federal government volunteers likened the tent complex to a jail-like “dystopian summer camp,” saying he witnessed an incident in which a migrant boy cut himself with a wire from a surgical mask.

“They just did not want to be there because they felt it was a jail,” the federal employee, who requested anonymity to speak freely, told CBS News. “Getting no status updates destroys those kids’ mental health. Everyone is terrified of being forgotten.”

Wednesday’s whistleblower complaint said federal volunteers who were demobilized left Fort Bliss with “serious concerns about the welfare and safety of the children who remained and who would be housed there in the future.”

Operations at Fort Bliss are now mainly managed by contractors hired by several private companies. The two whistleblower complaints by the Government Accountability Project have questioned whether these companies, which do not appear to have previous child welfare experience, can adequately care for hundreds of unaccompanied minors.

“Federal detailees witnessed significant waste, fraud and abuse. When they attempted to express their concerns to federal managers they were told — time and again — it was the contractors that were in charge and government employees needed to be responsive to the contractors’ needs,” Wednesday’s complaint said.

HHS has so far not allowed journalists inside the Fort Bliss tent camp, which opened in late March. CBS News has made several requests.

The department did not immediately respond to requests to comment on Wednesday’s complaint. Last month, HHS said it was working to improve conditions at Fort Bliss.

“We take our humanitarian mission and the well-being of children in our care seriously,” the department said then.

Upon returning to their regular posts, some federal volunteers received guidance from HHS instructing them not to share “any specifics” about Fort Bliss with journalists, friends or even colleagues and family members, citing a need to safeguard the “privacy and safety” of migrant children, according to an email reviewed by CBS News.

“The chance to step out of my comfort zone and focus on creative problem solving was invigorating,” read one of the generic messages that HHS instructed volunteers to use to describe their experiences at Fort Bliss.