New intelligence chief's wife blows his cover on Facebook

London: The new head of MI6 has been left exposed by a major personal security breach after his wife published intimate photographs and family details on the Facebook website.

Sir John Sawers is due to take over as chief of the Secret Intelligence Service (SIS) in November, putting him in charge of all of Britain's spying operations abroad.

But his wife's entries on the social networking site have exposed potentially compromising details about where they live and work, who their friends are and where they spend their holidays.

Amazingly, she had put virtually no privacy protection on her account, making it visible to any of the site's 200 million users who choose to be in the open-access 'London' network - regardless of where in the world they actually were.

Lady Shelley Sawers' extraordinary lapse exposed the couple's friendships with senior diplomats and well-known actors, including a leading character in The Archers, and revealed that the intelligence chief's brother-in-law - who holidayed with him last month - is an associate of the controversial Right-wing historian David Irving.

Immediately after The Mail alerted the Foreign Office to the astonishing misjudgment, all trace of the material - which could potentially be useful to hostile foreign powers or terrorists - was removed from the internet.

The move suggests that MI6 or the Foreign Office, which is also responsible for the GCHQ electronic eavesdropping centre, had not vetted what sort of information Sawers and his family were distributing over the internet.

Nor does it appear that the new intelligence chief - who will be codenamed 'C' once he takes up his post - had considered the potential risks of what his family was revealing to the world.

Foreign Office staff are warned about their use of social networking sites when they join the department, but MI6 expects its agents to maintain an even tighter secrecy, telling them not to reveal their true role to all but their closest family.

Sawers, currently Britain's Ambassador to the United Nations, where he sits on the highly sensitive Security Council, began his working life in MI6 but has spent the past 20 years building a career as a diplomat rather than a spy.

Who is to blame in this situation? Are the consequences of human error magnified on the internet? Tell us below.