The most devastating account of Cambodian genocide was under Pol Pot’s Khmer Rouge. S-21 was a former school converted into an interrogation center that held as many as 17,000 people within four years. Less than 10 people survived this center. The captives were tortured for days, beaten to death and thrown in mass graves. About 6,000 photographs have surfaced of the victims, but nearly every photo was separated from its record folder. The majority of the identities are still unknown.