The Ministry of Defence says that similar missile defence systems have been deployed at all recent Olympic Games.
They will be in place by mid-July, along with Royal Navy helicopter carrier HMS Ocean (which will be moored in the River Thames), Royal Air Force Typhoon jets (which will be temporarily stationed at RAF Northolt), and Puma helicopters (at a Territorial Army centre in Ilford).
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A round the world yacht race set off from London today on a year long journey which will see them circumnavigation the globe.
The shortlist for the ugliest buildings in the country has been finalised with four of them coming from London.
Hundreds of thousands of people turned out for the Notting Hill Carnival today with the weather just managing to hold off.