27 May 2012 Last updated at 10:53 GMT

BMX: GB rider Liam Phillips breaks collarbone

British Olympic hopeful Liam Phillips tumbles over his handlebars

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British Olympic hopeful Liam Phillips breaks his collarbone at the BMX World Championships in Birmingham.

Phillips, 23, was taken to hospital after tumbling over his handlebars and now faces a race against time to recover for the start of the Olympic BMX event on 8 August.

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