According to NBC News: The United States Capitol was placed on lockdown mid-Thursday afternoon following reports of shots fired in the vicinity of the chamber.
The reports of gunshots were unconfirmed. The House recessed shortly after indications of gunshots. The Senate went into a quorum call — that is, dispensed momentarily with its official business — shortly thereafter.
Missouri Sen. Claire McCaskill tweeted: Shots fired outside the Capitol. We are in temporary lock down.
Colorado Rep. Jared Polis tweeted: There had been some short of shooting here at the capital, we r on lockdown awaiting more info
Congress has been locked for the past week and a half in a contentious debate over funding the government, a disagreement in which contributed to a government shutdown that came to pass at the end of Monday.
UPDATE: (3:10P EST)
More Details Emerge about the incident in DC:
CNN’s Athena Jones, who was at a Senate office building near the Capitol, said she heard gunshots that sounded like fireworks. The FBI dispatched units in response to reports of shots near Garfield Circle, which is on the Senate side of the Capitol.
House and Senate sessions were immediately suspended.
A Capital Police bulletin said reports of gunshots required “all occupants in all House office buildings to shelter in place.”
“Close, lock and stay away from external doors and windows,” the bulletin said.
Authorities later lifted the lockdown, Bash later reported.
UPDATE: 3:25 PM EST
Source tells ABC News: a child was found unhurt in car of possible suspect in US Capitol Shooting.
(From Twitter) a photo of a car crashed into a guard shack near the Capitol Shooting. Unconfirmed if this is the car of the suspect.