Over the past six months politicians, advisers and journalists in and around Parliament were targeted by “spear phishing” on WhatsApp, in an apparent digital version of the honey trap employed by spies for decades.

The men were sent a series of increasingly intimate messages on social media, seemingly in the hope that the targets would compromise themselves, leaving them exposed to blackmail.

The platform may be modern, but the tactics – sometimes crude, sometimes highly elaborate – have a long and infamous history.

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