An Australian immigration official inadvertently sent the personal information to the organisers of the Asian Cup soccer tournament, according to The Guardian, which saw an email from the immigration department outlining the breach.
The revealed information included the passport numbers and visa details of the leaders, who included German Chancellor Angela Merkel, British Prime Minister David Cameron, Chinese President Xi Jinping and Japanese Prime Minister Shinzo Abe.
"The personal information which has been breached is the name, date of birth, title, position nationality, passport number, visa grant number and visa subclass held relating to 31 international leaders (ie prime ministers, presidents and their equivalents) attending the G20 leaders summit," the email said, according to the newspaper.
The email continued: "Given that the risks of the breach are considered very low and the actions that have been taken to limit the further distribution of the email, I do not consider it necessary to notify the clients of the breach."
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