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David Cameron: 9/11 lessons must be learnt

10 September 2011 Last updated at 08:59 BST

David Cameron has said that the world must "learn the lessons" from the 9/11 attacks about how to deal with violent Islamic extremism.

Speaking ahead of the 10th anniversary of the terrorist atrocity, the British prime minister said that despite progress in some areas of the world, dangers still existed.