The worsening security situation in Afghanistan over the past four years has led to over 14,000 "grave violations" against children, including nearly 3,500 deaths, a UN report says.
UN Secretary-General Antonio Guterres condemned "the alarming level" of grave violations committed by all parties and the fact that children "continue to bear the brunt of the armed conflict."
Some 9,000 children have been also injured in the same period, the report says.
Of serious concern, Guterres said, was that the children verified to have been killed or injured in 2015-18 represented almost one-third of all civilian casualties. That was "an increase of 82 percent in child casualties compared with the previous four years," he wrote.
The report, the fourth on children and armed conflict in Afghanistan, said the rise was traced to "an increase in child casualties resulting from ground engagements, explosive remnants of war, and aerial attacks."
According to the document, child casualties from air strikes "have significantly increased since 2015," reversing a reduction in numbers during the four preceding years. The UN verified 1,049 child casualties from air strikes in 2015-18, including 464 killed.
The report said that figure represented 40 percent of civilian casualties from aerial attacks.
Guterres said he was "extremely concerned," by the high numbers of children killed and injured as a result of "aerial operations conducted by government and pro-government forces."
The UN chief said armed groups were responsible for 43 percent of child casualties -- 3,450 killed and 9,149 wounded. Government and pro-government forces were responsible for 30 percent of child casualties, Guterres said.
The report says that while the UN also verified the recruitment and use of 274 children by armed groups and government forces, the actual number of children recruited and used in the Afghan conflict "is estimated to be much higher," citing reports that over 3,000 children were recruited, mainly by armed groups in 2016.
It also documented sexual violence against 13 boys and four girls, but Guterres indicated that the actual number was higher, saying that rape and other forms of sexual violence against children "is known to be underreported as a result of prevailing social norms, fear of retaliation, and impunity."