Swat Valley, Pakistan (CNN) -- The Sabaoon School for boys in northern Pakistan is anything but average. Nestled amid the bucolic charm of the Swat Valley's fertile terraced fields and steeply rising crags it looks idyllic. But if you get up close, a harsher reality becomes clear. Two army check-posts scrutinize visitors entering the sprawling site. Once inside, the high razor wire-topped walls around the classroom compounds create a feeling reminiscent of a prison. The boys here, aged 8 to 18, were all militants at some point. Some are killers, some helped build and plant improvised explosive devices, and others were destined to be suicide bombers until they were captured or turned over to the Pakistani army. All of them are at the school to be de-radicalized.
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Sabaoon School in Pakistan's Swat Valley works to de-radicalize local youth
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U.N. Special Rapporteur: U.S. drone strikes here have radicalized a new generation
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Up to 3,500 people have been killed in Pakistan by U.S. drone strikes since 2004
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Between 18% and 23% of those killed were not militants, according to one report
In early March he spent close to a week in @placeholder meeting government officials and tribal leaders, some of who claim to have lost family members in strikes.