Human rights campaigners have reacted furiously after a US student based in Scotland unmasked himself as the author of the "Gay Girl in Damascus" blogs, which charted the security crackdown in Syria.

Tom MacMaster, a 40 year-old Edinburgh University masters student, admitted that he was "Amina Abdallah Arraf", who had described herself as a Syrian political blogger.

Al Jazeera's Jonah Hull reports.