Speaking to ITV News ahead of tonight's switch on in Oxford Street, Jessie J said Christmas helped put London in a good mood - which was what the capital sometimes needed.
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A 25-year-old man has been arrested for urinating on the Cenotaph in Whitehall and pulling down commemorative wreaths.
As many as 60 bands in beautiful costumes are taking part in the grand finale of the Notting Hill Carnival parade today.
Smoke was seen for miles around today after a Wetherspoon pub caught fire in south east London.