Mark Nonkes from World Vision attended the ceremony where the children were set free and said it's the largest release of child soldiers ever in the country.
He told Premier: "That moment was just absolute jubilation. The children were excited, their families were excited, and the community was excited. Everyone was very happy that these children were released from their duties in the armed fighting."
The charity said although the release is a major victory, many of the children have been active in fighting, and some have experienced sexual and gender-based violence.
"They've been through literal hell," Nonkes said.
"We've talked to children who have been forced to shoot family members. We've talked to children who have been sexually assaulted. Almost all of them were abducted, some at school, some on their way to a garden. They've witnessed the worst humanity has."
Fifteen-year-old Victor is among the children released. He was abducted and forced to be an informant for an armed group for more than a year.
"They told me to go near the road and if I heard the sound of a car coming, I went and reported it," he explained. "Then they would come and take the car. They would shoot at it [and] they would burn it. The people inside the cars would sometimes escape and run. Other times they would be killed."
Case workers with World Vision's reunification and reintegration programme, supported by UNICEF, will help support the children to recover from the violence they have witnessed and re-join society.
Suggesting a long road ahead for the children, Nonkes: "They have survivor's remorse in some cases. In other cases there's just absolute excitement that they don't have to do this anymore.
"Children are grasping with what they've been forced to do and how to make sense of that. We've got a big job ahead of us with this counselling work."
Listen to Mark Nonkes speaking with Premier's Tola Mbakwe here:
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