The United Nations says the Islamic State group is systematically killing, torturing and raping children and families of minority groups in Iraq, and it is calling on Iraqi government forces to do more to protect them. In a report issued in Geneva, the U.N. Committee on the Rights of the Child (CRC) said it has received reports of "several cases of mass executions of boys, as well as reports of beheadings, crucifixions of children and burying children alive." Iraq's military has been struggling in its fight against Islamic State, and the government has asked repeatedly for more weapons and training. Still, the U.N. agency urged that more be done, saying Iraq needs to "take all necessary actions to ensure the safety and protection of children and their families." "We are really deeply concerned at torture and murder of those children, especially those belonging to minorities" CRC committee expert Renate Winter told a news briefing. "The scope of the problem is huge." Children targeted are from the Kurdish and Christian communities as well as young Muslims, Winter said. "We have had reports of children, especially children who are mentally challenged, who have been used as suicide bombers, most probably without them even understanding," Winter told Reuters. Videos online show that children below 8 years and younger are being trained to be soldiers. The Islamic State group is a former al Qaeda affiliate that has killed thousands and forced hundreds of thousands to leave their homes after seizing significant amounts of territory in Syria and Iraq since 2013. It is currently the target of an international military campaign led by the United States.