Gunfire in the House?

Via anonymous emailer, the following unsettling report:

Police sealed off the Capitol on Friday after receiving reports of gunfire in a House office building across the street.

Capitol police are investigating "the sound of gunfire in the garage level of the Rayburn House Office Building," said an announcement on the internal Capitol voice alarm system.

The Senate was in session at the time, but the House was not.

Rep. Peter Hoekstra, R-Mich., conducting a House Intelligence Committee hearing, interrupted a witness to request those attending the meeting to remain in the room and said the doors must be closed.

"It's a little unsettling to get a Blackberry message put in front of you that says there's gunfire in the building," he said.

Drudge provides the text message:

Police sealed off U.S. Capitol Friday after reports of gunfire in House office building across street...
Blackberry message: This is a message from the U.S. Capitol Police
1. If you are in the Rayburn HOB then Shelter in Place. Quickly move into the nearest interior office space or interior hallway and away from windows. The Capitol Police are investigating reports of gunfire in the Rayburn HOB.
2. If nearby, grab Go-Kits and personal belongings.
3. Close doors behind you, but do not lock.
4. Remain calm.
5. Await further instructions. Do not leave the building.

UPDATE:
The Washington Post has a few more details, though there is nothing concrete about the incident that sparked the lockdown and emergency response.

UPDATE:
Reuters is reporting that while the lockdown was lifted for a brief time, it was again imposed on the Rayburn HOB. No reports of injuries or arrests at this time.

Police were investigating the sound of gunfire in the garage level of the Rayburn building, which houses offices of members of the House, officials said. The lockdown barred people from entering or leaving Capitol buildings.

"We have no reports of injuries at this time," Kimberly Schneider, public affairs officer for the Capitol police, told a news conference. A Reuters reporter saw a person being wheeled out of the Rayburn building on a stretcher. Schnedier said if somebody was on a stretcher it could have been unrelated.


Police said earlier there was a firing range two floors away from the garage and the Rayburn building and tunnels below the Capitol remained closed during the police investigation.

Senate Sergeant at Arms Bill Pickle told Reuters there were no reports of any arrests or injuries though several ambulances were brought to the scene.

"We have been told by staff of shots fired and the smell of smoke," Pickle said. He later raised the possibility that a firecracker might have been the cause.

UPDATE:
The US Capitol has been reopened, but the Rayburn building remains closed due to further investigations. The WaPo has streaming video from the news briefing.

UPDATE:
The noises that sounded like gunfire? Construction crews were working in the area and used equipment that made such sounds. The office buildings have been reopened.