(Reuters) — Usually concerned with top secret matters affecting national security, Britain’s eavesdropping spy agency GCHQ was also on the lookout for leaks of a yet-to-be-published Harry Potter book, its publisher has revealed.

Shortly before the publication of one of the volumes in J.K. Rowling’s seven-part wizarding saga, with millions of fans worldwide at a fever pitch of anticipation, publisher Nigel Newton received an unexpected phone call.

“I remember the British spy eavesdropping station GCHQ rang me up and said ‘we’ve detected an early copy of this book on the Internet’,” Newton told Australia’s ABC Radio in an interview last week that gained attention in Britain on Sunday.

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