The United Nations says thousands of children in 20 conflict situations around the globe were killed, maimed, recruited, abducted or sexually violated in 2016.
The annual blacklist on children in armed conflict names and shames abusers.
Issued Friday, the report verifies more than 4,000 serious violations by government forces from nine nations and 11,500 violations by 55 nonstate armed groups, including the Islamic State group, the Taliban, Boko Haram and al-Shabab. In those violations, more than 8,000 children were killed or maimed.
"We have to assume that this is just the tip of an iceberg," Virginia Gamba, U.N. special representative on children and armed conflict, told reporters Friday at the study's launch.
Gamba said verification is often difficult, so it is reasonable to assume "there are things that fall through the cracks," and that the real figures are much higher.
Among the violations for which the U.N. monitors, there was an increase across the board in 2016, a worrying trend, she noted.
The report found the recruitment and use of children as child soldiers in Somalia and Syria more than doubled compared with figures from 2015.
While in Afghanistan, the U.N. verified more than 3,500 child casualties — the highest number ever recorded. In the Democratic Republic of the Congo, the number of children killed and injured was the highest in that country since 2012.
The denial of humanitarian access was also singled out for concern. The report found that children were trapped in besieged areas or deprived of access to food, water and medical assistance, including vaccines.
The United Nations works with cooperative parties listed in the report to implement measures to reduce violations against children and to lead to the release of those who are child soldiers or detainees.
Saudi Arabia on blacklist
The Saudi-led coalition in Yemen was also listed for the killing and maiming of 683 children and for airstrikes that hit 33 schools and 19 hospitals in the war-torn country.
Last year, there was a diplomatic row between the Saudis and the U.N. when the kingdom was briefly blacklisted. Riyadh threatened to pull funding from critical humanitarian programs, leading then-U.N. chief Ban Ki-moon to remove it from the list.
The U.N. said this year that the Saudis have taken steps to try to cut casualties, including agreeing to install a child protection unit at coalition headquarters.
"For me, this is a critical year," Gamba said. "The past is unchangeable, but we can do something to change the present and the future."
Gamba, who took up her post in mid-May, has changed the format of the report to separate parties who do not take measures to protect children and those who do. Saudi Arabia was on the latter list.
"We reject the inaccurate and misleading information and figures contained in the report," Saudi Arabia's U.N. Ambassador Abdullah al-Mouallaimi told a news conference Friday. The Saudi ambassador had at least seven other coalition ambassadors with him in a show of support.
Houthi rebels blamed
He put the blame for the child casualties on the Iranian-backed Houthi rebels, who led a coup to oust the Yemeni government in September 2014 that resulted in the fighting.
The U.N. report also held the Houthis accountable for 414 child casualties and the recruitment of 359 children as fighters, porters or checkpoint guards. There were also over 220 reports of denial of humanitarian access, most of which were attributed to the rebels.
"Naming perpetrators responsible for attacks on children is a critical first step in correcting these wrongs," said Eva Smets, executive director of Watchlist on Children and Armed Conflict, a global network that advocates for children's rights. "The U.N. must now work with the Saudi Arabia-led coalition and other parties to ensure these horrific violations of vulnerable children are never repeated."