The House Committee on Oversight and Reform convened Thursday to question acting Secretary of Homeland Security Kevin K. McAleenan about children held in migrant detention facilities and border security.

In an intense exchange, committee Chairman Rep. Elijah E. Cummings questioned McAleenan about his department’s transparency on the state of the facilities holding migrant children. “We are the United States of America, we are the greatest country in the world. We are the ones that can go anywhere in the world and save people,” Cummings said.