The Capitol and surrounding office buildings were briefly evacuated after a small airplane entered restricted airspace over Washington.

The evacuation was ordered about 1:30 p.m. Saturday.

Two F-16 fighter jets intercepted the plane after it entered restricted airspace and was out of communication with air traffic control. A Capitol Police spokeswoman said the pilot of the aircraft did not immediately communicate after it flew into restricted space, and that’s what led to the evacuation.

The incident prompted authorities to institute an AIRCON RED, air condition red, alert, police told CNN. The alert is triggered when an aircraft enters restricted airspace in Washington without authorization.

Also evacuated was the Library of Congress and the U.S. Supreme Court buildings, the Metropolitan Police said.

A U.S. official said that the pilot’s destination was Mount Airy, where he was going to meet his daughter. The source says the pilot said his outdated maps caused him some confusion. There was one other person in plane.

The alert was lifted about 2 p.m. after the pilot began communicating, and visitors and staff were allowed back into the buildings.

The Secret Service says its agents will interview the pilot, in line with protocol. The agency says the incident didn’t affect security at the White House. The jets escorted the plane to the airport in Mount Airy, North Carolina, where the pilot was met by members of law enforcement.

NBC affiliate WWLP reports that the airplane took off from Westfield-Barnes Regional Airport.

President Barack Obama was playing golf at a military base in Maryland at the time.

Airspace violations by small planes are common in Washington. The Capitol was briefly cleared and the White House was temporarily locked down when a single-engine plane wandered into restricted airspace in April 2009.It was also evacuated in January 2011 when a commercial airliner accidentally entered restricted airspace.