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Tornadoes rip through Oklahoma http://t.co/swf1QgQvhN

Article written by Mark Mardell
Mark Mardell
North America editor
Tornadoes rip through Oklahoma http://t.co/swf1QgQvhN
Article written by Katty Kay
Katty Kay
Presenter, BBC World News
Oklahoma Medical Examiner confirms 51 people were killed by the mile-wide tornado.
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