The post quickly went viral, causing Facebook to publish a statement, quashing the false rumour.

BBC: Privacy groups call for Facebook changes U-turn

Events on Sunday seemed to underline his point, when fans of two of the most heavily debt-laden clubs - Roma and Lazio - forced the referee to abandon the Rome derby after a false rumour that a child had been killed by police.

BBC: AC Milan football club

Other days, as when a (false) rumour crackles through a nearby slum that 100-rupee notes will be dished out to those who sign up, hordes pour in.

ECONOMIST: India��s UID scheme

Rumour has it that he is a former soldier, bent on revenge for false imprisonment, and that he chooses his targets carefully.

ECONOMIST: Robin Hood in the Atlas