LONDON - British military commanders say they are training to deal with a "9/11-type attack" as they launched a major exercise to test their readiness for the 2012 London Olympics.
As jet fighters took to the sky with nine weeks to go to the opening ceremony, the Olympic Park was getting its biggest try-out as the final wave of sporting test events got under way.
Four Royal Air Force (RAF) Typhoon fighter jets flew into the British capital to herald the start of Exercise Olympic Guardian, a nine-day training operation to test the response to a possible air attack during the Games.
Military helicopters were stationed around the capital, including on the amphibious assault ship HMS Ocean in the River Thames, with some carrying sniper teams.
AWACS surveillance planes and air-to-air refuelling aircraft will also be airborne during the exercise.
Airspace restrictions will be in place throughout the July 27-August 12 Games.
Air Vice-Marshal Stuart Atha, air component commander for Olympics air security, said their plan had several levels and "will allow us to deal at one end ù which is that 9/11-type attack ù perhaps down to the lower and the slower type of threat that we may face."