Flights to LAX were temporarily halted Sunday as the FAA cited a shortage of air traffic controllers linked to the ongoing federal government shutdown.

The Federal Aviation Administration said flights departing for Los Angeles International Airport were halted Sunday morning due to a staffing shortage at a Southern California air traffic facility.

The FAA issued a temporary ground stop at one of the world’s busiest airports soon after U.S. Transportation Secretary Sean Duffy predicted that travelers would see more flights delayed and canceled in the coming days as the nation’s air traffic controllers work without pay during the federal government shutdown.

During an appearance on the Fox News program “Sunday Morning Futures,” Duffy said more controllers were calling in sick as money worries compound the stress of an already challenging job.