BEIRUT (AP) - Teenagers carrying weapons stand at checkpoints and busy intersections in Iraq's second-largest city, Mosul. Patched onto the left arms of their black uniforms are the logos of the Islamic Police.
In Raqqa, the Islamic State group's de facto capital in Syria, boys attend training camp and religious courses before heading off to fight. Others serve as cooks or guards at the extremists' headquarters or as spies, informing on people in their neighborhoods.
Across the vast region under IS control, the group is actively conscripting children for battle and committing abuses against the most vulnerable at a young age, according to a growing body of evidence assembled from residents, activists, independent experts and human rights groups.
In the northern Syrian town of Kobani, where ethnic Kurds have been resisting an IS onslaught for weeks, several activists told The Associated Press they observed children fighting alongside the militants. Mustafa Bali, a Kobani-based activist, said he saw the bodies of four boys, two of them younger than 14. And at least one 18 year old is said to have carried out a suicide attack.
In Syria's Aleppo province, an activist affiliated with the rebel Free Syrian Army said its fighters encountered children in their late teens "fairly often" in battles against the rival Islamic State group.
It is difficult to determine just how widespread the exploitation of children is in the closed world of IS-controlled territory. There are no reliable figures on the number of minors the group employs.
However, a video posted on militant websites Monday offered the most substantive evidence to date that the militant group enlists children. It purportedly highlights the so-called "Cubs of the Caliphate" class, showing young children dressed in black training to use different weapons, responding to staged ambushes and learning to manufacture explosives. The video corresponded with AP reporting.
But a United Nations panel investigating war crimes in the Syrian conflict concluded that in its enlistment of children for active combat roles, the Islamic State group is perpetrating abuses and war crimes on a massive scale "in a systematic and organized manner."
The group "prioritizes children as a vehicle for ensuring long-term loyalty, adherence to their ideology and a cadre of devoted fighters that will see violence as a way of life," it said in a recent report.