The Guardian reports: One of Rupert Murdoch’s most senior European executives has resigned following Guardian inquiries about a circulation scam at News Corporation’s flagship newspaper, the Wall Street Journal.

The Guardian found evidence that the Journal had been channelling money through European companies in order to secretly buy thousands of copies of its own paper at a knock-down rate, misleading readers and advertisers about the Journal’s true circulation.

The bizarre scheme included a formal, written contract in which the Journal persuaded one company to co-operate by agreeing to publish articles that promoted its activities, a move which led some staff to accuse the paper’s management of violating journalistic ethics and jeopardising its treasured reputation for editorial quality.

Internal emails and documents suggest the scam was promoted by Andrew Langhoff, the European managing director of the Journal’s parent company, Dow Jones and Co, which was bought by Rupert Murdoch’s News Corporation in July 2007. Langhoff resigned on Tuesday.