The Trump administration has tracked down 146,000 unaccompanied migrant children who came over the U.S.-Mexico border during the Biden administration and were lost after the government released them to unvetted sponsors, according to senior officials.Acting Attorney General Todd Blanche and Homeland Security Secretary Markwayne Mullin announced on Thursday a massive increase in the number of children the government had been able to locate since last summer, when just 22,000 had been found.“We found 146,000 kids so far. 146,000 kids. We still have nearly 300,000 missing,” Mullin said during a press conference at the Justice Department’s Washington headquarters Thursday morning. “When we start digging into these cases, and you start hearing the absolute horrific things that took place underneath the Biden administration, either true neglect at best and criminal at worst, to allow 450,000 kids to go missing throughout this country.”

Under the Biden administration, more than 10 million foreigners were apprehended attempting to enter the United States illegally from Mexico, including more than half a million children who arrived without a parent or guardian. Those children were released into the U.S., and the Department of Health and Human Services Office of Refugee Resettlement was responsible for placing each child with a vetted sponsor through court proceedings.