House Republicans hounded the Biden administration’s top border official, Alejandro Mayorkas, on Tuesday for allowing millions of illegal immigrants to roam the country rather than be held in federal detention facilities while they await immigration court proceedings.

GOP lawmakers on the House Homeland Security Committee attempted to poke holes during a hearing on Capitol Hill into Mayorkas’s statements that the Department of Homeland Security wants to detain more immigrants at U.S. Immigration and Customs Enforcement detention centers but was stretched too thin financially to do so.