Cannon House Office Building evacuated due to suspicious vehicle: Sources

The Cannon House Office Building, a congressional office building, was evacuated via underground routes Thursday morning due to a suspicious vehicle.

The Cannon House Office Building, a congressional office building in Washington, D.C., was evacuated via underground routes Thursday morning due to a suspicious vehicle, according to a law enforcement sources. The Capitol Police in a tweet called it "an active bomb threat investigation." Messages have been sent to congressional staffers asking that they "remain calm and relocate to Longworth House Office Building using the underground tunnels." The Library of Congress is also being evacuated, sources told ABC News.