Sickening new video appears to show a boy shooting dead an ISIS hostage . Extremism experts say children are now being indoctrinated from terrorists . Fears it will create ' generation who know nothing other than ISIS . ' Videos released by terrorists reveal tough military training children overseas . Former unnamed soldier was pressured into signing up for suicide missions .
Sickening new video appears to show a boy shooting dead an ISIS hostage . Extremism experts say children are now being indoctrinated from birth . Fears it will create 'generation who know nothing other than ISIS ideology ' Videos released by militants reveal tough military training children undergo . Former child fighter was pressured into signing up for suicide missions .