The Federal Aviation Administration (FAA) shared on Sunday it had grounded flights in the Washington, D.C. area for roughly an hour due to radar problems. 

In a Twitter thread, the agency shared that it paused departures to D.C.-area airports due to repairs being made to a communications system at the Potomac Terminal Radar Approach Control facility, noting that the facility switched to a backup system. 

The FAA later announced that departures from area airports have resumed and repairs to the communications power panel were complete.

“During the repairs, a back-up system handled communications safely,” The FAA said in its Twitter thread. “Normal operations are resuming.”

A spokesperson for the Metropolitan Washington Airports Authority (MWAA) told the Washington Post that departures from Ronald Reagan Washington National Airport and Dulles International Airport were subjected to ground stops. 

Officials also said that flights from Baltimore/Washington International Thurgood Marshall Airport and Richmond International Airport were affected as well, the Washington Post reported.