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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As people across London celebrate Christmas, Micah Community Church share their Christian beliefs of the special day.
Police are now investigating the 'unexplained' death of a 23 year old man from Erith who was found dead in June.
Most of the squatters who took over the former RBS HQ on Trafalgar Square to feed homeless people on Christmas day have been evicted.