Fast trains between Didcot and Oxford, and Paddington and Oxford are cancelled. Stopping services are running every 30 minutes.
Flooding between Swindon0Bristol Parkway is causing delays of up to 15 minutes between London Paddington and Cardiff Central. Updates soon.
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The 34-year-old from Coulsdon in Surrey died during the private party in Headley in the early hours of Monday, Surrey Police said.
The Home Office made the arrests at various restaurants across London on July 4.
Mayor of Newham Sir Robin Wales criticised the International Olympic Committee on the fourth anniversary of the opening ceremony.