The BBC was the latest media company to be targeted by the Syrian Electronic Army, which says it is "supporting the Syrian people against #FSA (Free Syrian Army) terrorism".
Others targeted in the past include the Agence France-Presse news agency, whose @AFPphoto account was taken over last month and images purporting to be from the warzone in Syria were posted.
The group has previously claimed credit for hacking the Twitter and Facebook accounts of Sky News Arabia, Al-Jazeera Mobile, German broadcaster German Deutsche Welle, France 24 and Israeli newspaper Haaretz.
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