3 August 2012 Last updated at 20:53

Olympics: Rebecca Adlington beaten by Katie Ledecky

American 15-year-old Katie Ledecky stunned Rebecca Adlington to take the women's 800m freestyle Olympic title, with the British favourite third.

Ledecky took off at a stunning pace and maintained her lead, leaving defending champion Adlington and Danish rival Lotte Friis floundering.

Ledecky finished in eight minutes 14.63 seconds, four seconds clear of second-placed Mireia Belmonte Garcia.

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