Today marks seven years since the 7/7 terrorist attacks in London.
Four terrorists detonated bombs in the morning rush-hour, three on the underground railway and a fourth in Tavistock Square on board a double-decker bus.
Wreaths have been laid on behalf of Prime Minister David Cameron and Mayor of London Boris Johnson at the Hyde Park memorial to the victims.A minute's silence is set to be observed at a meeting at City Hall this evening.
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The operation carried out by Westminster City Council led to the seizure of £8,000 worth of cigarettes.
Armed troops have been stationed around Parliament to free up armed police to patrol the streets in the wake of the Manchester bomb attack.
Chelsea had planned an open top bus tour to show off the Premier League trophy and hope to add the FA Cup in Saturday's final with Arsenal.