All flights in and out of Reagan National Airport in the Washington, D.C., area came to a halt Monday morning because of a fire alarm in the control tower. The Federal Aviation Administration said the order to stop all flights went out just before 10:45 a.m. and is slated to remain in effect until noon. The FAA statement did not say whether any fire was found in the tower. Reagan airport was the site of the nation’s deadliest plane crash since 2001 when an Army helicopter collided with an American Airlines jet in the skies over the capital and killed all 67 people aboard both aircraft.