Witnesses on Tuesday told the House Homeland Security about the inhumane conditions faced by unaccompanied migrant children who cross the southern border, many of whom are trafficked before and after entering the country.

Witnesses included a human trafficking expert, the former high-ranking official at an unaccompanied minor site, and a retired border patrol agent. Together, their testimony painted a grim picture.

Ali Hopper, a human trafficking expert, said she visited a path used by migrants lined with what cartels refers to as “rape trees,” areas where minor migrants are forced to perform sexual acts to help pay for their journey. According to Hopper, underwear hung from the branches of one such tree.

Hopper said the pathway was also lined with discarded passports and other IDs, “often burned, torn, or buried,” including the passport of a five-year old Colombian girl. While criminal migrants often enter the country under false names to avoid detection, Hopper said changing children’s identity raises “darker questions.”

“Are they being exploited? What horrors have they endured to reach this point?”

More than half a million children have entered the United States without parents and been sent by the U.S. government to live with “sponsors” in recent years. Sponsors do not have to be related to the children and, because they are typically illegal immigrants themselves, they are not reliably vetted.

“Criminal sponsors are defrauding the U.S. government by using this government program as a logistical chain in their trafficking operation,” Tara Rodas, the former deputy at an unaccompanied minor processing site, told the panel. “These children are not merely victims, they are hostages.”

Rodas said it was “unclear why we’re luring children to the United States to be the white-glove delivery system” for gangs. She called for the government to “implement simple safety measures like DNA testing for children and their sponsors,” and “stringent penalties like prison for sponsors who are unable to produce the children they are in charge of.”

By the time the Office of Refugee Resettlement makes its 30-day follow-up phone call — until recently, the only post-release outreach it made — a third of unaccompanied migrants are missing, according to The New York Times. That means more than 165,000 children could be missing in the country.

President-elect Donald Trump has said locating and rescuing the missing migrant children will be one of his administration’s top priorities. Fraudulent “sponsors” who take custody of children and then lose them could form a list of priority deportees in the Trump administration.

The Biden administration this year temporarily shuttered a program for adult migrants after it became clear that a massive number of “sponsors” were lying about their identity. But the Biden administration has not released information about the minor resettlement program, going so far as ignoring subpoenas.

During Tuesday’s hearing, Rep. Clay Higgins (R-LA), chairman of a border security subcommittee, laid the blame for the unaccompanied minor migrant crisis at the White House’s feet.

“The Biden-Harris administration has stated that they have the most humanitarian immigration policy in history,” he said, “but there’s nothing humanitarian about [this].”

Hopper observed that those who defended the current system were not treating migrant children with the same compassion that they would American children.

“American citizens can’t just deflect from agencies like Child Protective Services and say ‘oh, my kids are fine, you don’t need to check on them,’ you wouldn’t take their word for that,” she said.

Rep. Glenn Ivey (D-MD), the ranking member on the committee’s oversight panel, is one of the few Democrats in Congress who has acknowledged the migrant crisis.

“I actually share in the concerns of my colleagues about the dangers and the horrors that these children face, and that the system has let them down when they get to the United States,” Ivey said Tuesday.

The Democrat said he heard of children forced to work in dangerous factories and other “horrific circumstances.”

“We need to figure out how to work our way out of that,” Ivey said. “It’s gonna be expensive to locate these kids, it’s gonna be expensive to try and put them back in connection with their parents.”

Rep. Lou Correa (D-CA), the ranking Democrat on the border security panel, acknowledged the trafficking and said those profiting off children should be punished. He said “we need more resources for more home visits” of children in the sponsor’s home.

But Rep. Dan Bishop (R-NC) said money wasn’t the issue. He blamed policies that give unaccompanied minors special treatment, which, he says, have the perverse effect of actually encouraging families to split up. This has not only put children in danger, he said, but caused a rise in human trafficking in the United States.

“You have chosen to recreate in the United States to a certain degree the horrific circumstances that are causing people to flee elsewhere,” Bishop said.

“The federal government has precipitated and is facilitating this humanitarian catastrophe,” he added. “The Biden administration was so focused on moving people through the system as fast as possible that they failed to ensure the safety of the children they were releasing,” he said.

“Many of these children already suffered at the hands of criminal cartels on that treacherous journey to the border, only to find themselves exploited again after being released from government custody,” Bishop said. “This impossible-to-understand bad judgment is simply heartbreaking and tragic.”

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