In his first UK TV interview US whistleblower Edward Snowden has given the BBC new details of GCHQ's ability to hack users' smart phones without their knowledge. Mr Snowden, a former analyst with the US National Security Agency (NSA) told Panorama there was "very little" the public could do to stop GCHQ - the British government's digital spy agency - getting control of their handsets. He described a series of intercept capabilities named after Smurfs - the little blue imps of Belgian cartoon fame. The UK government declined to comment on "intelligence matters". Watch Peter Taylor's film: Edward Snowden, Spies and the Law on Panorama on BBC One and YouTube for Free.

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