This weekend, travelers felt the effects of the federal government shutdown.

Newark Liberty International Airport was hit with multiple ground stops on Sunday due to air traffic control staffing shortages. According to FlightAware, there were 449 delays and 123 cancellations. Officials with the New York City Emergency Management Department say the average delays for departing flights were about two hours, with some flights more than three hours late.

Travelers have experienced similar delays out of LaGuardia and John F. Kennedy International airports in New York, and airports nationwide have seen ground stops, including Boston, Dallas, Austin and Las Vegas.

U.S. Secretary of Transportation Sean Duffy appeared on “Face the Nation with Margaret Brennan” this weekend and warned that delays and cancellations are “going to get worse.” He also stated that the government would halt air traffic if need be, adding, “We’re not going to let that happen.”