Syrian children suffered the most war-related violations in 2016 as military conflicts and political games in the embattled country waged on for the sixth year, UNICEF's latest research showed.

There were more verified records of killing, injuring and recruitment of children last year compared to 2015, according to UNICEF's "Hitting rock bottom: How 2016 became the worst year for Syria's children" report, which was released Monday.

About 652 Syrian children were killed last year alone, and more than one-third of the deaths having occurred at or near a school, the report showed. The number of child deaths had climbed by 20 percent from the previous year and was the worst since child casualties documentation started in 2014.

Another 850 children were recruited to fight in the conflict in 2016 and some extreme cases included children recruited as executioners, suicide bombers or prison guards, UNICEF said.