(The Hill) - A large absence of air traffic controllers across the country are causing thousands of flight delays, as the government shutdown stretches onto its 20th day, the Federal Aviation Administration (FAA) said Monday.

About 7,850 flights within, into, or out of the U.S. were delayed on Sunday, according to FlightAware. Over 1,000 flights have been delayed so far on Monday.

FAA has chalked up delays in Atlanta, Chicago, Dallas and Newark over the weekend to staffing issues, according to Reuters. The FAA also noted possible delays in Las Vegas and Phoenix due to shortages.

"As [Transportation] Secretary [Sean] Duffy has said, there have been increased staffing shortages across the system. When that happens, the FAA slows traffic into some airports to ensure safe operations,” a FAA

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