Shots Fired on Capitol Hill?

CNN reporting possible shots fired near Rayburn House office building.

Sound of gunfire heard in Rayburn building garage.

There are no reports of injuries or suspects.

The Senate side seems to be all quiet.

Drudge has the Blackberry message sent by Capitol police to Rayburn staffers:

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.

Reuters reports the smell of smoke in the Rayburn lobby.

Ambulances are on the scene, but that's just a precaution. No activity reported near them. This sounds pretty low-key, like they're being careful, but not overly concerned that there's a gunman on the loose.

UPDATE: Capitol Police press conference at noon.

The folks in Rep. Jack Kingston's office are blogging from Rayburn right now.

UPDATE 2:57p.m.: Breitbart has more on the in-depth, floor-by-floor search being conducted right now.

Michelle notes a possible eye-witness account of a gunman.

I was just on Capitol Hill, on the Senate side, and all was normal.

UPDATE 4:07p.m.: Rayburn gunfire was likely an air hammer, says CNN.