Wednesday, May 11 2005 22:06 Hrs (IST) - World Time -

Washington: The US Capitol and White House were briefly evacuated today (May 11, 2005) after a small plane entered restricted airspace over the city.

Security officials in several other Government buildings, including the Treasury Department and the US Supreme Court, ordered people to safer locations. Military aircraft scrambled over the city.

President Bush was away from the White House, biking at Patuxent Wildlife Research Centre in Beltsville, Vice President Dick Cheney, in the White House, was moved to a "secure location" elsewhere, said a senior administration official, speaking on condition of anonymity.

Congressional leaders were hustled from the Capitol by armed officers.

A Cessna 150 aircraft breached the security zone over Washington, law enforcement officials said, prompting alerts across the city.

"Out of an abundance of caution, the appropriate security measures consistent with this type of violation went into effect," said Homeland Security spokesman Brian Roehrkasse.

The plane was approached by a fighter aircraft and veered away, officials said according to a Federal Aviation Administration official speaking on condition of anonymity.

But in the meantime, armed security officers raced through the Capitol shouting for people to leave. "This is not a drill," guards shouted as they moved people away from the building.

Large black armoured SUVs often used by House and Senate leaders sped away from the Capitol as a military jet flew overhead.

The incident sparked a flurry of emergency activity throughout the capital, which was targeted on Sept 11, 2001 and has been under a heightened state of alert since then.

Washington's Reagan National Airport has been closed to general aviation since the Sept. 11 attacks. In the 3 1/2 years since then, hundreds of small planes have flown within the restricted airspace around the capital - a 15 3/4-mile radius around the Washington Monument.

However, it's rare for fighter jets to be scrambled.