U.S. Capitol police were on the scene as a small helicopter, described as a gyrocopter, landed on the Capitol lawn.
Media outlets are reporting that the pilot broke restricted airspace.
Cox Media Group's political insider Jamie Dupree was one of the first reporters to report what was going on, and posted this photo to his Twitter feed shortly after the pilot landed.
The pilot's identity or motive have not been released.
A Florida man, however, was named by The Tampa Bay Times as the pilot.
>>Report: Florida man tries to land helicopter on U.S. Capitol lawn
Doug Hughes, a mailman from Ruskin, Fla., had planned to fly a gyrocopter to send a "campaign reform message to Congress," the The Tampa Bay Times reported.
The area is shut down as police investigate.
The Capitol had been under lockdown, but it has since been lifted.
But vistors around the Capitol complex were able to capture the landing on video. The Associated Press has posted it to its YouTube account.
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