In Pictures: Cambodia Remembers Khmer Rouge’s House of Horrors

Cambodia mourns for victims of the Khmer Rouge regime on a day when 40 years ago the nightmare came into existence.

Several hundred Cambodians and Buddhist monks gathered at the former execution ground to remember the day when 40 years ago the country fell to the Khmer Rouge.

The regime held power for four years during which an estimated 1.7 million Cambodians died from starvation, slave labor and wholesale murder and bloody purges.

After Khmer Rouge was overthrown in January 1979, the burial pits of the execution site were excavated and the skulls of the victims were put in a stupa as a reminder of what the country endured.

Forty years later and 6,000 miles away, John Gunther Dean, former US ambassador to Cambodia, recalls what he describes as one of the most tragic days of his life - April 12, 1975, the day the United States “abandoned Cambodia and handed it over to the butcher.”

The human skulls of victims in Khmer Rouge regime are on display at the stupa at Choeung Ek memorial on the outskirts of Phnom Penh, Cambodia. (Photo: AP/Heng Sinith)

A woman stands in front of the stupa containing hundreds of human skulls and bones of victims in Khmer Rouge regime at the Choeung Ek memorial. (Photo: AP/Heng Sinith)

Cambodians pray in front of a stupa containing hundreds of human skulls and bones of victims at the Choeung Ek memorial. (Photo: AP/Heng Sinith)

Cambodian main opposition Cambodia National Rescue Party leader Sam Rainsy (left) prays in front of a stupa at the Choeung Ek memorial. (Photo: AP/Heng Sinith)

A Cambodian woman burns incense sticks as she prays in front of the stupa. (Photo: AP/Heng Sinith)

German Ambassador to Cambodia, Joachim Baron Von Marschall (left) pulls ribbon during an opening ceremony of the Memorial in Tuol Sleng Genocide Museum in Phnom Penh, Cambodia. The letters on a memorial reads: Never will be forgotten the crimes committed during the Democratic Kampuchea regime. (Photo: AP/Heng Sinith)

Cambodian Deputy Prime Minister Sok An, prays a Buddhist monk, during an opening ceremony of the Memorial in Tuol Sleng Genocide Museum. The memorial built at Toul Sleng Genocide Museum to remember at least 12,000 people tortured and killed there during the radical Khmer Rouge regime. (Photo: AP/Heng Sinith)