In the suburbs of Phnom Penh, Cambodia is a nondescript complex of buildings known as Tuol Sleng. A former high school, it was used as a detention and torture center by the Khmer Rouge, who came to power in 1975 after a civil war.

Led by Pol Pot, the Khmer Rouge was responsible for the deaths of an estimated 1.7 million Cambodians through execution, starvation and forced labor during the three years the regime was in power.

An estimated 17,000 prisoners came to Tuol Sleng, including 2,000 children. Of the 17,000, there are only 12 known survivors.

Tuol Sleng is now a genocide museum. Visitors can see the rooms where prisoners were held, and the implements of torture that were used to extract confessions. One can also look into the faces of more than 8,000 of those who were killed, preserved in photographs taken by their Khmer Rouge captors.

Seventeen miles outside of Phnom Penh is Choeung Ek, a former orchard where many of the Tuol Sleng prisoners were executed and buried in mass graves. The remains of 8,985 bodies have been exhumed from graves scattered among the trees. Many of these remains are now housed in a memorial stupa, erected in 1998.

Earlier this year, the Cambodian government convened a special court to bring the surviving senior Khmer Rouge leaders to justice. Five suspects have been indicted, including Khang Khek leu, who headed the Tuol sleng torture center. Pol Pot is not among the five. He died in 1998 before being brought to justice.

Prisoner photographs on display at Tuol Sleng.