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NSA 'abuses phone database for political purposes'

17 January 2014 Last updated at 01:52 GMT

The US National Security Agency (NSA) has collected and stored almost 200 million text messages a day from around the world, UK media report.

The NSA extracts and stores data from the SMS messages, and UK spies have had access to some of the information, the Guardian and Channel 4 News say.

Beth McLeod reports.