(CNN) Militants with black masks stand by as 15-year-old Mohammed watches a video of fighters cutting off a man's head.
"This is jihad for the sake of God," the men with Kalashnikov rifles say.
Mohammed begins to feel lost, confused. "Does God want me to do jihad?" he wonders.
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This is Mohammed's eyewitness account, told to CNN on Wednesday in a telephone interview.
He was one of the more than 140 Kurdish schoolboys kidnapped in Syria last month by the Islamic State in Iraq and Syria (ISIS) and forced to take daily lessons in radical Islamic theology, the Syrian Observatory for Human Rights, a London-based monitoring group, and local activists say.