Flights were prevented from leaving Ronald Reagan National airport after a gunman shot 12 people dead and seriously injured three others at the Washington Navy Yard, a naval installation in the US capital.
The Federal Aviation Administration stopped outbound flights at the Reagan airport but incoming aircraft were allowed to land as helicopters searched for the gunman, who was later killed in a gun battle with the police.
Outgoing flights since resumed but were subject to some delays, the airport said.
The Navy Yard is about 5 miles from the airport and some planes pass over the site on their way in and out Reagan National.
The gunman, 34-year-old Aaron Alexis from Fort Worth, Texas, is believed to have been an ex-US Navy serviceman.
