Hundreds of staff at the agency responsible for maintaining the U.S. nuclear stockpile were fired Thursday in the wave of mass Trump administration terminations, multiple current and former employees told ABC News.

Hundreds of probationary employees were terminated Thursday night in the mass Trump administration layoffs. The move prompted concerns of a national security risk because the agency is responsible for maintaining U.S. nuclear weapons, transporting them, and nuclear counterterrorism, among other missions.