The dreaded Islamic State militant "Jihadi John" was a "reasonably hardworking" student and showed no sign of radicalisation, his former UK school principal said on Monday.
In a one minute and 17 second video, he is seen wearing a black hood with his face uncovered for the first time on camera.
Britain Siddhartha Dhar, a British Hindu who converted to Islam and now goes by the name Abu Rumaysah.