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Washington zoo's twin tiger cubs pass swimming-proficiency test

7 November 2013 Last updated at 16:41 GMT

A pair of three-month-old Sumatran tiger cubs have passed a swimming proficiency test at Washington's Smithsonian National Zoo.

It may have been an unwelcome introduction to the world of survival for the cubs - named Bandar and Sukacita - but zookeepers say it was necessary to make sure they could survive if they fell into the protective moat which surrounds their enclosure.

Katy Hastings reports.