Patrick Semansky | AP
The Capitol Police Twitter feed warned the public to “please stay away from this area.
In addition to Capitol police, Washington police were at the scene, some of whom had gas masks.
People at the Cannon House Office Building received an alert telling them to leave that building and relocate to the Longworth House Office Building.
The FBI Washington Field Office’s National Capital Response responded to the scene, as did agents from the Bureau of Alcohol, Tobacco and Firearms.
Congress is currently in recess.
The White House was monitoring the situation, and getting updates from law enforcement.
This is breaking news. Please check back for updates.
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