Three former child soldiers from Africa announced the launch of a new U.N.-backed advocacy group Thursday to help other kids escape and heal from war.

The three survivors, all in their 20's and living in the U.S., say the group aims to create a global network of young people like themselves who can get rehabilitated with the help of education.

"The key was discovering I could do other things than just fight," said Ishmael Beah, who wrote a best-selling memoir about being pressed into service in his native Sierra Leone's civil war at age 13. "I learned to use my mind."

Beah, who also is a UNICEF's advocate for children affected by war, will lead the new U.N.-backed "knowledge-based advocacy group" against the use of child soldiers. He fought for almost three years before UNICEF rescued him.

The U.N. says the number of child soldiers around the world is estimated at 250,000.

Grace Akallo said becoming a child soldier taught her to "kill or be killed." She recalled being taken into captivity for seven months as a teenager, along with 139 other girls snatched from her school, by a rebel group in northern Uganda that forced them to fight against the Uganda government.

Kon Kelei, the third former child soldier, said he was taken into a camp in southern Sudan when he was just 5 years old and told that it was school.

"An AK-47 is not meant for a kid. It's not meant for a human being, let alone a kid," he said. "Rehabilitation is actually what made me who I am and what I'm talking about today."

Radhika Coomaraswamy, the top U.N. envoy on children and armed conflict, said the group and their stories could serve as examples of "the power of resilience."

In February, she told the U.N. Security Council that 58 groups in 13 countries still recruit and use child soldiers and that children in several countries are also killed, maimed, abducted and raped and denied access to humanitarian groups.