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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Across the country people are pledging to run 3.7 miles in memory of Matt Campbell who died while taking part in the London Marathon.
Jonathan Munro is giving evidence during the latest stage of a High Court trial in London.
But while he wasn't showing it, PC Tyler O'Hare was enjoying every minute of it.