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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The man, believed to be in his 60s, was attacked on Friday morning on Hamilton Road in Southall.
Since the UK's busiest airport began operation in 1946 more than 20 million flights have taken off.
London mayor Sadiq Khan is "extremely worried" about knife crime as Met Police revealed there was an increase in stabbings in the capital.