Homeland Security Secretary Markwayne Mullin told reporters that the Trump administration has located at least 146,000 unaccompanied minors who were lost during the Biden administration. 

Major cities, such as New York, Chicago and Los Angeles, have refused to cooperate with federal immigration enforcement as a result of their sanctuary cities policies, the New York Post reported. 

“If you can’t stand for law enforcement to go find these kids, who are you? Who are you? And do you know where we’re finding the most of them: sanctuary cities," Mullin said in a press conference on Thursday. 

In an August 2024 report, the Department of Homeland Security Office of Inspector General said the Biden administration had lost hundreds of thousands of missing migrant children. Between fiscal years 2019 and 2023, more than 448,000 unaccompanied minors were held in U.S. Immigration and Enforcement facilities. 

They were then transferred to the Department of Health and Human Services for resettlement with domestic sponsors. Of those, 291,000 migrant children were never issued notices to appear in federal immigration courts after HHS released them, and 32,000 never showed up for their court dates. The rest are considered missing, according to the report.