(CNN) -- As a teenager in war-ravaged Sierra Leone, Ishmael Beah was brainwashed, drugged and forced to kill.
"We went from children who were afraid of gunshots to now children who were gunshots," says Beah who became separated from his family at just 12 years old when his town was attacked.
He says his family was later killed in the country's vicious civil war, which lasted from 1991 to 2002.
During this period rebel groups like the Revolutionary United Front (RUF) -- who were notorious for hacking off limbs and indoctrinating children into their struggle -- fought government forces and their offshoots for control of the diamond rich West African state.
Desperate for help, Beah says he wandered the countryside with a group of other children who had lost their families in similar circumstances.
They managed to avoid the roaming RUF rebels but witnessed gunfights, ransacked villages and countless dead bodies along the way.
"I saw a man carrying his son that had been shot dead, but he was trying to run with him to the hospital," Beah recalls.
"(There was also) this woman had been running and she had a baby that was tied on her back. She'd been running away from the fighting and the bullet had struck the baby and the baby had been killed but she didn't know."
Eventually Beah and his friends came across a rural camp they initially believed to be an army base.
They soon realized however that they had in fact stumbled upon a battalion of breakaway Sierra Leonean soldiers. The splinter group opposed the RUF but were pursuing similarly vicious fighting tactics, including the deployment of child soldiers. Beah was taken in, given shelter and eventually trained to kill.
"Somebody being shot in front of you, or you yourself shooting somebody became just like drinking a glass of water. Children who refused to fight, kill or showed any weakness were ruthlessly dealt with.
"Emotions weren't allowed," he continued. "For example a nine-year-old boy cried because they missed their mother and they were shot," he says of the era which was portrayed in the 2006 Hollywood film "Blood Diamond," starring Leonardo DiCaprio and Djimon Hounsou.
Speaking about the moment he became separated from his family, Beah recalls: "I had gone to a talent show, I was interested in American hip-hop music, with my older brother, to another town and my town was attacked. I went from having an entire family to the next minute not having anything. It was very painful."
Now a U.N. goodwill ambassador, a law graduate and a best-selling author, Beah is heading the fight to publicize the plight of child soldiers in Africa.
"I do work with UNICEF to go to some of these places, but also to meet the young people who are coming from these experiences to reassure them that it is possible to come out of this," he says.
"I can speak to these children. With proper integration this is the way you can have a successful removal of children from armed groups"
Beah says he now has a greater understanding as to why children are viewed as such valuable fighting assets to groups like the RUF across Africa.
According to the United Nations there remains an estimated 300,000 children involved in conflicts around the world today.
"Everybody always asks why do they go after children? Because you can easily manipulate them," he says.
"They also want to belong to something, especially if they live in a society that has collapsed completely. Their communities are broken down, they want to belong to anything slightly organized and these groups become that."
Beah felt this acceptance in his division of child soldiers and fought with the group for two years before eventually being rescued by UNICEF.
He was taken to a rehab center in the Sierra Leone capital, Freetown, where he spent eight months learning about what happened to him and readjusting to life after the war.
Those who worked at the center were frequently attacked by child soldiers finding it difficult to adapt to their new surroundings in the early days.
"We were very angry. We were very destructive. We destroyed the center where we were staying at (and) we burned some things up," he says of his early months there.
"We beat up the staff members. They came back, we beat them up some more."
With time, and the patience of a carer named Nurse Esther, however, Beah says he was eventually able to reconnect to his lost childhood and remember the person he once was.
He also credits the hip-hop music he loved as an innocent 12-year-old and the songs of Bob Marley as a major help in his recovery.
Beah's progress was so impressive that in 1996 he was selected to go to the United Nations and speak to a conference led by Graca Machel, Nelson Mandela's wife, on the plight of child soldiers.
It was during this trip that he would meet Laura Sims -- a UNICEF worker who would eventually adopt him and bring him to America when the conflict in Sierra Leone escalated to engulf Freetown in 1998.
Upon moving to the U.S., Beah enrolled at the United Nations school in New York before going on to graduate with a law degree from Oberlin University in Ohio.
During his studies he also wrote a book on his experiences as a youth in Sierra Leone, "A Long Way Gone: Memoirs of a Boy Soldier".
"I finished this book before I graduated. I never intended to publish it but the idea for writing it was really this desire to just find a way to give the human context that was missing in the way the issue of child soldiers were discussed," he says.
His passion for bringing a greater understanding to the experiences of child soldiers has since led Beah to his current role as a U.N. ambassador for children affected by war.
And he hopes to offer the same support to today's child soldiers as Nurse Esther and the staff at the Freetown rehab center offered him.
"I witness UNICEF workers doing all of this and when these children were removed I felt their confusion," he says.
"I've been in that place before. All of a sudden you no longer have your military gear, you're now a kid."
"What I'm saying to them is that everybody has the capacity to find their own talent with the right opportunities to do something more with their lives, and everybody can walk their own path."