The agency is investigating an automation problem at an air traffic center in Leesburg, Virginia, FAA spokeswoman Kathleen Bergen said. The center handles high-altitude air traffic for a region that includes Baltimore-Washington International Thurgood Marshall Airport, Washington's Reagan National Airport and Dulles International Airport.

The FAA said it is directing high-altitude flights around the affected airspace. The problem is not believed to be caused by any accident or hacking.

American Airlines said in a tweet that air traffic control issues are impacting all East Coast flights. The airline is urging passengers to plan accordingly. Laura Nedbal, an American spokeswoman, said its flights from Cleveland to the Washington area were also affected.