Sen. Rand Paul, R-Ky., threatened to delay a confirmation hearing for Lance Schroyer, who Trump announced in June was his choice to be the permanent director of the U.S. Immigration and Customs Enforcement agency. 

The threat was made during a closed-door briefing with senior officials in the Department of Homeland Security, the Wall Street Journal reported, citing unnamed sources. 

Paul has previously criticized how the Trump administration has handled a string of shootings by ICE agents, and he told the officials he wouldn't hold the hearing until he received more information about the shootings of two American citizens by ICE officers in Minneapolis. 

Schroyer has been facing internal opposition from administration officials, including Trump's border czar Tom Homan, since Trump announced his nomination due to his lack of experience in federal government and immigration.