By AMANDA SEITZ and ALANNA DURKIN RICHER

WASHINGTON (AP) — President Donald Trump’s administration is conducting a nationwide, multi-agency review of 450,000 migrant children who crossed the U.S.-Mexico border without their parents during President Joe Biden’s term.

Trump officials say they want to track down those children and ensure their safety. Many of the children came to the U.S. during surges at the border in recent years and were later placed in homes with adult sponsors, typically parents, relatives or family friends.

Migrant advocates are dubious of the Republican administration’s tactics, which include dispatching Homeland Security and FBI agents to visit the children. Trump’s zero-tolerance approach to immigrants in the U.S. illegally — which has resulted in small children being flown out of the country — has raised deep suspicion his administration may use the review to deport any sponsors or children who are not living in the country legally.

Trump officials say the adult sponsors who took in migrant children were not always properly vetted, leaving some at risk for exploitation. The Department of Justice has indicted a man on allegations he enticed a 14-year-old girl to travel from Guatemala to the U.S. and then falsely claimed she was his sister to gain custody as her sponsor.

Trump officials will do house checks and interviews

Trump officials expect more problematic sponsors will surface as the administration conducts door knocks and interviews to check on cases in which complaints — about 65,000 of them since 2023 — have been filed. This year, about 450 cases with complaints have been referred to federal law enforcement officials, according to a senior Health and Human Services official who was not authorized to publicly discuss details of the review and spoke on the condition of anonymity.

“We’re combing through every report, every detail — because protecting children isn’t optional,” HHS said in a social media post on X. Health Secretary Robert F. Kennedy Jr. appeared to reference the review during a Cabinet meeting with Trump on Wednesday, saying his agency was trying to “find the children.”

For at least a decade, the federal government has allowed adults to apply to house migrant children who crossed the border without a parent or legal guardian. The program, however, was plagued with problems during the Democratic Biden administration years as officials struggled to process an influx of thousands of children. Federal officials failed to conduct background or address checks in some cases before placing children with sponsors. In other instances, sponsors provided plainly false identification, a federal watchdog report last year concluded.

After that report was issued, the Biden administration said it had already worked to improve the issues through “training, monitoring, technology and evaluation.”

Thousands of kids were placed with legitimate sponsors

But thousands of children were also placed with legitimate families, some of whom now fear they’ll be swept up in the Trump administration’s review and targeted for deportation, said Mary Miller Flowers, the policy director of the Young Center for Immigrant Children’s Rights.

The center is assigned to work with some of the most vulnerable children who cross the border. Flowers said that many children have been placed with their parents, grandparents, cousins, aunts or uncles.

In some cases, children may arrive at the border separately from their parents who already live in the U.S. and reunite with them through the program.

“Now you have a situation where the government is checking on the wellness of children and encountering their undocumented parents and deporting their parents,” Flowers said. “I don’t know what about that is good for children.”

Government has taken custody of 100 kids

So far, about 100 kids in the past two months have been removed from their sponsors and put back into custody of the federal government, typically in private shelters, according to the health department official.

In Cleveland, federal prosecutors allege that one man, who was living in the U.S. illegally, arranged for the 14-year-old girl to get a copy of his sister’s birth certificate and then coordinated her journey from Guatemala to the U.S. He claimed to be her brother, but no fingerprinting or DNA testing was done to verify his claim, according to a senior Justice Department official who was not authorized to speak publicly and spoke on the condition of anonymity.

The man pleaded guilty to sexual battery of the child in Ohio state court in 2024 and was sentenced to eight years in prison, the official said. The man now faces federal charges including inducing illegal entry for financial gain and aggravated identity theft. Attorneys for the man declined to comment.

As part of the review, the Trump administration is working to identify the location of every child who has been placed with a sponsor, the Justice Department official said. Investigators are going through suspicious sponsorship applications, like so-called “super sponsors,” who have claimed to have family relationships with, in some cases, more than a dozen unaccompanied children, the official said.

Videos and reports of armed law enforcement officers showing up to conduct wellness checks at the doorsteps of unaccompanied minors and their sponsors have surfaced from across the country.

In an emailed statement, the FBI said that it is conducting “nationwide” welfare checks because “protecting children is a critical mission,” adding that it would continue to work with its “federal, state and local partners to secure their safety and well-being.”

But advocates have raised doubts that children will open up about abuse or other concerns about their sponsors to armed law enforcement officers from federal agencies who are simultaneously executing mass deportation campaigns.

H2The search for kids has resulted in deportation of some adults

In Hawaii, homeland security agents have been scouring Kona for unaccompanied minors and their sponsors, with two families deported as a result and another child put back into federal custody, according to a news report from the Honolulu Civil Report. Last month, a northern Virginia attorney posted video of five federal agents visiting the home of his client, who is awaiting a green card, for a welfare check. And in Omaha, a 10-year-old who came to the U.S. unaccompanied about three years ago and was placed with his uncle was visited by armed agents in “black, tactical gear” two weeks ago, according to his attorney. He was asked a series of questions, including the status of his case and the whereabouts of his sponsor, according to his attorney Julia Cryne.

“They’re using this as a way to go after the kids,” Cryne said. Her client, she added, has recently had his application for a green card approved.

H2New rules make it more difficult for sponsors

The Trump administration has dramatically altered the way the sponsorship program works. It’s cut funding for the attorneys who represented the most vulnerable migrant children, leaving even toddlers or preschool aged-children with no federally-funded representation.

The administration has also rolled out a number of new rules for adults who want to sponsor a migrant child, according to guidance obtained by the Associated Press. In recent weeks, the office began requiring sponsors to submit fingerprinting, DNA testing and income verification to strengthen its screening procedures.

That could be a hurdle for many sponsors who may not have an income or might be undocumented, Flowers said. Children cannot leave federal custody until they are released to a sponsor.

“They have put in a trifecta of policies that essentially make it impossible for them to leave federal detention,” Flowers said.

Beatrice Dupuy in New York contributed.