Update at 3:15 p.m.: All lanes are now reported to be back open.
Arlington police are preparing to close Jefferson Davis Highway (Route 1) at the Reagan National Airport overpass, near Crystal City, due to a report of a downed power line.
Firefighters are on the scene and requested the busy artery be closed in both directions, according to scanner traffic.
No word yet on how long the road will be closed.
A look at some of the millions of fans who line the roads every year in the sizzling heat of the French summer.