The nation's capital was given the green light Wednesday afternoon about one hour after a small airplane violated restricted airspace over the city, forcing the rapid evacuation of the White House, the U.S. Capitol Building (search) and the Supreme Court around noontime.

A pilot and student pilot, en route from Pennsylvania to an air show in North Carolina, were taken into custody after their flight sparked a frenzy of activity that tested the capital's post-Sept. 11 response system. The government decided not to press charges.

"The two men in the plane have been interviewed, and it has been determined that the intrusion into restricted airspace appears to have been accidental. And no charges are being sought at this time," said Homeland Security spokesman Brian Roehrkasse.

Two F-16 military jets scrambled over to Washington from Andrews Air Force Base just outside the city in Maryland. The jet pilots met the plane, which came within four miles of the U.S. Capitol and three miles of the White House, and escorted it out of the Air Defense Identification Zone to Frederick, Md., about 50 minutes northwest of the city. The jets then returned to the air base.

The men were identified as Hayden Sheaffer, of Lititz, Pa., and Troy Martin, of Akron, Pa., according to a federal law enforcement official who spoke on condition of anonymity.

The plane — a small two-seat, high-wing Cessna 152 (search) — was registered to Vintage Aero Club, a group of people who fly from Smoketown Airport in Pennsylvania's Lancaster County, said club member Merv King. Former club member John E. Henderson said the plane was to be flown by Sheaffer and Martin to an air show in Lumberton, N.C.

Sheaffer confirmed he had been released by authorities but declined to comment further when reached on his cell phone by The Associated Press.

Martin's wife, Jill, said: "Troy was discussing with me last night after they made their flight plans all about the no-fly zones and how they were going to avoid them. He said they were going to fly between two different restricted areas."

The Pentagon was not evacuated and the mood there was described as "business as usual." However, North American Aerospace Air Defense (search), which operates in part out of the Pentagon, coordinated with air and Homeland Security officials.

Police in Washington shouted at lawmakers, staff members, media and tourists to run from the buildings. About 20 minutes later, the evacuations were cancelled.

The pilot, who was said to have entered the restricted space then exited and re-entered before being warned out of the area with four flares, was ordered to touch down in Frederick.

President Bush was not at the White House at the time of the evacuation. He was taking part in a bike ride at Patuxent Wildlife Refuge outside the city. The president headed back to the White House after his motorcade was cleared for return.

First lady Laura Bush and visiting guest Nancy Reagan, the former first lady, were at the White House and taken to a secure location there.

Also at the White House, press were informed about the evacuation after a Secret Service agent stuck his head into the briefing room and screamed, "Get out! Evacuate!" A reporter than passed on the message.

An alert that was supposed to go out over the public announcement system did not happen, according to FOX News White House reporters. However, White House Press Secretary Scott McClellan said that an alarm was sounded.

Many reporters who started to run out of the briefing room were told by Secret Service uniformed officers to get back into the building and get downstairs. Moments later they started shouting again: "Get out of here! Out! Off the grounds!"

Not everyone found out about the evacuation, though, and not everyone got out of the White House, according to FOX News' reporters. Many press members were left in the basement and in other areas of the White House.

McClellan said even if the situation appeared confused, Secret Service evacuated the building as soon as the threat level went to orange from yellow at 12:01 p.m. EDT when the plane was 10 miles from the White House. At 12:03 p.m., the alert level went to red, at which time the plane was about three miles from the White House. The alert level went back down to yellow at 12:11 p.m. when the plane was flying away from the city with a jet escort. The Secret Service alert system uses the same color codes as the one used by the Department of Homeland Security, but the system predates the one created by DHS, McClellan said.

"Security precaution protocols were followed in this instance," McClellan said. "We are grateful for the job the Secret Service does" as well as the other security officials who helped move people to more secure locations, he said.

Asked whether the evacuation demonstrated to terrorists how vulnerable Washington, D.C., still is to attack, McClellan said: "We have to remember that we are a nation at war and there are still people who seek to do harm to the United States and who seek to carry out attacks against the United States."

At the Capitol, Majority Leader Bill Frist and Minority Leader Harry Reid both went to the floor of the Senate to praise the performance of U.S. Capitol Police, who also yelled at people: "Run, this is not a drill."

However, John Loftus, a security analyst and FOX News contributor, said that the evacuation plan showed major flaws in the federal government's security plan.

"Almost nothing worked — this small plane should never have gotten within four miles" of the Capitol, Loftus said, adding that the plane was too small to puncture the walls of the building and a "running evacuation" of the federal buildings should not have been called.

The evacuation was the most urgent since President Reagan's funeral last June, when officials lost track of an arriving plane carrying Kentucky Gov. Ernie Fletcher a little more than an hour before Reagan's casket was to arrive at the Capitol to lie in state.

The Associated Press contributed to this report.