Cambodia inaugurates memorial to Khmer Rouge genocide victims at Tuol Sleng museum

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, Thursday, March 26, 2015. 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, has been official inaugurated Thursday. The letters on a memorial rads: Never will be forgot the crimes committed during the Democratic Kampuchea regime. (AP Photo/Heng Sinith) (The Associated Press)

German Ambassador to Cambodia, Joachim Baron Von Marschall, second from right, prays a Buddhist monk, left, during an opening ceremony of the Memorial in Tuol Sleng Genocide Museum in Phnom Penh, Cambodia, Thursday, March 26, 2015. 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, has been official inaugurated Thursday. (AP Photo/Heng Sinith) (The Associated Press)

Cambodian Deputy Prime Minister Sok An, center, prays a Buddhist monk, left, during an opening ceremony of the Memorial in Tuol Sleng Genocide Museum in Phnom Penh, Cambodia, Thursday, March 26, 2015. 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, has been official inaugurated Thursday. (AP Photo/Heng Sinith) (The Associated Press)

Cambodian officials have inaugurated a memorial at the Toul Sleng Genocide Museum to remember at least 12,000 people tortured and killed at the site when it was a Khmer Rouge prison.

Buddhist monks chanted prayers at Thursday's ceremony, attended by Cambodia's deputy prime minister and representatives from the United Nations and the Khmer Rouge tribunal.

The museum, formerly a high school in Cambodia's capital, Phnom Penh, was turned into S-21 prison after the Khmer Rouge took power in 1975. Of the estimated 16,000 men, women and children who passed through its gates, only a handful survived.

An estimated 1.7 million people died as a resulted of the Khmer Rouge radical polices from 1975 to 1979.

The Buddhist stupa replaces a similar memorial that disintegrated inside the Tuol Sleng complex.