Sickening footage allegedly released by ISIS appears to show children playing mock execution games as they train for roles in the terror group. The video shows several children kneeling next to a wall while an adult appears to pretend to shoot them in the head. Another clip shows a child slitting the throat of a stuffed toy with a knife. And it's not the first video of so-called ISIS children released in recent weeks. Other chilling footage shows the terror group giving young boys military training. The clip shows the youngsters being drilled in battle techniques and firing deadly assault rifles. They are wearing military fatigues and headbands proudly displaying the black flag of Islamic State. ISIS has need of fresh recruits after suffering a series of major military setbacks at the hands of Iraqi government forces and Kurd warriors, backed by air strikes from the US-led coalition.