Baghdad - The UN children's fund warned on Thursday that 3.6 million Iraqi children are at "serious risk" of death, injury, sexual violence, abduction and recruitment into armed groups, and has called on warring parties in Iraq to protect their rights.In a report titled "A Heavy Price for Children," Unicef said that the number of children in Iraq at serious risk of death or wartime exploitation had increased by 1.3 million in the past 18 months.It described Iraq as "one of the most dangerous places in the world for children".The report said that the 2014 Islamic State group invasion of large areas of Iraq's north and west and the military operation to unseat them have had a "catastrophic impact", with about 4.7 million Iraqi children in need of humanitarian assistance.It said children were also affected by the lack of adequate health care, poor public services and the desperate state of education."Children in Iraq are in the firing line and are being repeatedly and relentlessly targeted," said Peter Hawkins, Unicef's Iraq representative. "We appeal to all parties for restraint and to respect and protect children. We must help give children the support they need to recover from the horrors of war and contribute to a more peaceful and prosperous Iraq."Unicef called for an urgent action to protect children's rights in war-torn Iraq. It appealed for humanitarian access to all children across Iraq, including in ISIS-controlled areas, to improve education and to provide psychological and recreation programs.Unicef said it was short of funding and was seeking $100m for its 2016 programmes in Iraq.Iraq is going through its worst crisis since the 2011 withdrawal of US troops. In the summer of 2014, ISIS militants blitzed across large swaths of the country's north and west, capturing Iraq's second-largest city of Mosul and the majority of the western Anbar province.ISis has since suffered major defeats when Iraqi forces, backed by US-led coalition, drove the extremists out of several key cities, including the city of Fallujah, which was retaken by Iraqi forces earlier this week. ISIS extremists still control significant areas, including Mosul.