Over 4,000 child soldiers in wars
The United Nations has documented more than 4,000 cases of children recruited and used in conflicts last year and said in a report that thousands more are estimated to have joined armies and rebel groups around the globe.
UN secretary-general Ban Ki-moon's annual report on children and armed conflict adds Nigeria's notorious extremist group Boko Haram to the UN "list of shame".
It now includes eight government forces and 51 armed groups that recruit or use, kill or maim, or commit sexual violence or rape against children in conflicts, or attack schools or hospitals.
The report said the recruitment and use of children in armed conflict remained prevalent last year and those who commit grave violations against children, especially sexual violence, usually do not face justice.
Leila Zerrougui, the special representative for children and armed conflict, told a news conference launching the report that advances by Islamist extremists in Iraq "are creating extremely volatile and dangerous conditions for children".
She said the secretary-general has listed four new parties recruiting and using children: Islamic State of Iraq and the Levant, al Qaida-affiliated Jahbat al-Nusra, ultra-conservative Islamic rebel group Ahrar al-Sham, and the Kurdish People Protection Units or YPG.
In Nigeria, Ms Zerrougui said, "Boko Haram continues to commit unspeakable violence against children."
She said its listing for killing and injuring youngsters, attacking schools and abducting girls will allow the United Nations to collect and verify information about its activities and "take action".
Mr Zerrougui also said recruitment and use of children is widespread in South Sudan and gains made by the government to address grave violations have been reversed following fighting that broke out in December which has sparked months of ethnic attacks.
She said president Salva Kiir and former vice-president Riek Machar, whose forces have been fighting, recently pledged to stop using child soldiers.
In the Central African Republic, Ms Zerrougui said, children have been used by Muslim and Christian rebel groups and been victims of widespread violence including sexual attacks "in total impunity". In 2014, children in the conflict-torn nation "continue to face unspeakable violence", she said.
Children growing up in Somalia, Congo and Afghanistan also continue to suffer the consequences of conflict but Ms Zerrougui cited one bright spot - Chad has been taken off the "list of shame" because its national army has implemented all measures to protect children in an action plan signed with the UN.