Twitter user Helen True shared this photograph of emergency services attending London Bridge station where four people were taken ill.
Network Rail and TfL dismissed reports of a gas leak and said that overground and underground train services were running as normal.
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Harry Potter fans today get their first glimpse of the wizard's wife and son as character portraits are revealed ahead of the upcoming play.
Gary Barlow performed an impromptu gig in a busy shopping centre.
Stephen Hawking said a Brexit would make Britain more "isolated and insular".