GCHQ puzzle
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Thousands baffled as GCHQ's Christmas puzzle deadline looms

It is more than a month since the director of the government's intelligence service, GCHQ, came up with a rather tricky set of questions for the public as a bit of Christmas fun.

With just a few days to the deadline, more than 600,000 people have started the quiz, but no one has managed to get full marks.

Our security correspondent Gordon Corera has been taking a look.

  • 28 Jan 2016
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