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US-UK encryption hacking: 'Scale is surprising'

6 September 2013 Last updated at 11:05 BST

Documents from the former US intelligence contractor, Edward Snowden, suggest US and British security agencies have managed to unlock the internet encryption codes protecting the emails, banking and medical records of hundreds of millions of people.

The reports have been published by the New York Times and the Guardian in London.

Dr Herb Lin is the chief computer scientist at the United State's National Research Council.

He said he was surprised that the agencies would attempt to break encryptions on such a 'large scale'.

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