S-21
S-21 was a prison camp located in Phnom Penh, Cambodia, used by the Khmer Rouge from its rise to power in 1975 to its fall in 1979.Formerly the Tuol Svay Prey High School, it was converted into a center for detention, torture and interrogation of prisoners. It was headed by the notorious Khang Khek Leu (aka Duch), who worked closely with Khmer Rouge leader Pol Pot.
There are only seven known survivors of the prison.
S-21 is now the Tuol Sleng Museum and a memorial to those who died.
See also: The Killing Fields, Democratic Kampuchea