Aircraft that fail to comply with procedures within a restricted airspace zone around the Olympic site in London could be subject to “lethal force” from the military, it was revealed today.
RAF Typhoon fast jets and RAF Puma helicopters with snipers armed with hi-tech rifles will be among the military aircraft patrolling the restricted zone which comes into force from tomorrow.
Intercepted aircraft will be expected to comply with the directions of the military aircraft.
"As a last resort, we will have lethal force as an option," said Air Vice-Marshal Stuart Atha, the Olympics air security commander.
Asked who would give the order for lethal force to be used, AVM Atha said: "The highest level of Government makes that decision."
He said taking lethal action would be a "worst-case scenario" and that a best-case scenario would be to intercept and gain knowledge of the seriousness of the situation away from the built-up area of London.
AVM Atha was speaking at RAF Northolt in west London where some of the aircraft that will help patrol the restricted area were on display.
The restricted zone, in operation from midnight tonight to August 15, comprises a small inner zone covering central London and the Olympic site in Stratford, east London, and a large zone covering a swathe of south-east England.
The restricted zones are designed for general aviation which includes light aircraft, gliders and balloons. No commercial flights will be affected.
There will also be restrictions at the Olympic sailing venue at Weymouth in Dorset from tomorrow until September 8.
The air security plan includes:
:: RAF Typhoon fast jets based at Northolt;
:: RAF Puma helicopters with sniper teams, based at Ilford in east London;
:: Army Rapier and Starstreak ground-based air defence systems at six London sites;
:: Royal Navy Sea King helicopters based at Northolt;
:: Helicopter carrier HMS Ocean, the Navy's largest ship, which will be on the River Thames in London as a base for helicopter operations as well as accommodation for personnel.
At Northolt today, a Home Office spokesman said that for the Olympics "we are planning on a terrorist threat environment that is severe".
He added that it was better to be at the severe level in case the threat level needed to be increased.
But he went on: "We are not suggesting that there is any particular threat or risk to the Games that we know about."
The Civil Aviation Authority has written to all private pilots and distributed more than 60,000 leaflets to warn about the restrictions.
Under the plan, general aviation will not be allowed in the inner zone, although passenger planes heading for Heathrow and London City Airports will not be affected.
Private pilots wanting to fly in the larger restricted zone will have to file a flight plan and comply with Ministry of Defence instructions.
Details of how the Typhoon and the military helicopters will act if they are forced to intercept aircraft were released today.
Aircraft intercepted will have to rock their wings, follow the military aircraft and turn away from London.
Flares and lasers could be fired by the military aircraft, then, as a last resort, if an aircraft fails to comply with the directions of the military aircraft, it may be considered to be a threat to security, which may result in the use of lethal force.
Civil Aviation Authority airspace policy assistant director Phil Roberts said today that there has been a good response from the general aviation community to the plan.
"We shall be monitoring it over the weekend to see how it's going. We have made it clear that we are prepared to suspend pilots' licences in certain circumstances."
A smaller set of airspace restrictions will be put in place from August 16 to September 12 for the Paralympics.
Defence Secretary Philip Hammond said: "Whilst there is no reported threat to the London Olympics, the public expects that we put in place a range of measures aimed at ensuring the safety and security of this once-in-a-generation event.
"I am pleased to be able to confirm that the equipment necessary to operate our comprehensive, layered air security plan is now in place.
"I believe this will provide reassurance to residents of, and visitors to, London, and a powerful deterrent.
"There are now 17,000 military personnel involved in the Olympic security effort, every one of whom will play a part in ensuring the Games go smoothly and are the national sporting celebration they should be. They deserve everyone's gratitude."
The MoD said HMS Ocean is due to pass through the Thames Barrier and arrive at Greenwich in south east London at around 9pm tonight.
The mobilisation of volunteer reservists in support of the Olympics is also under way.