Islamic State: Teenage boy 'tortured for two days'

The Islamic State and other groups in Syria and Iraq are using children as young as 12 on the battlefield in the ongoing conflict there.

They are indoctrinated and receive weeks of military-style training.

Others suspected of co-operating with rival groups have been tortured and, in some cases, killed.

Ahmed was just 14 when IS captured and tortured him for two days.

He told the BBC's Quentin Sommerville about his ordeal.