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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Controversial police chief Cressida Dick was today named Scotland Yard's first woman Commissioner.
Police accidentally sent letters to seven people killed in the Croydon tram crash, inviting them to a survivors meeting.
The exhibition includes the gown she wore when she danced with John Travolta at the White House and a dress used for a Vanity Fair cover.