Ground Stop At Reagan National Airport, Fire in ATC Tower

Update (1913 EST):

Update (1835 EST):

At approximately 1745 EST, a Ground Stop was issued at Reagan National Airport in Washington D.C. due to a reported fire at the air traffic control (ATC) tower.

Dozens of eyewitnesses reported they were ordered to deplane as all incoming and outgoing flights were halted. Delays have already been announced at BWI and Dulles as airspace impacts begin to register.

This is developing.