Prosecutors on Tuesday began making their case against the Khmer Rouge's prison chief for crimes against humanity, saying he had a key role in the regime that killed two million Cambodians.

Only around a dozen people are known to have survived the notorious prison run by Duch, which is now a genocide museum lined with photographs of some of the more than 15 000 men, women and children who died there.

The frail-looking 66-year-old jotted down notes in the dock as prosecutors finally got their chance to begin laying out their arguments at the UN-backed war crimes tribunal, now under way after years of bickering and delays.

They said Duch, also known as Kaing Guek Eav, played a central role in the 1975-1979 communist Khmer regime's iron-fisted rule as head of the Tuol Sleng prison called S21.

"S21 formed an integral and indeed vital role in a widespread attack on the population of Cambodia," said co-prosecutor Chea Leang. "The accused's crimes were part of this attack."

Duch has denied personally torturing or executing prisoners but has taken responsibility for presiding over the prison in Phnom Penh. He is charged with crimes against humanity, war crimes, torture and premeditated murder.

Duch, who faces life in jail, said he acted under orders from superiors in the Khmer Rouge, which rose to power as a spinoff from the conflict in Vietnam and emptied Cambodia's cities to take society back to a rural "Year Zero."

Khmer Rouge leader Pol Pot died under house arrest in 1998, and many in Cambodia believe the UN-sponsored tribunal is the last chance to bring those regime figures still alive to justice.

"I have been waiting for this for so long," Om Chantha, who lost her husband under the regime, said at the court on Monday. "Even if he is sentenced to life in jail, he will still survive, but millions died."

Duch himself is expected to address the court about his role and publicly ask forgiveness from Cambodians. He became a born-again Christian during the 1990s.

The tribunal was formed in 2006 after nearly a decade of wrangling between the United Nations and Cambodian government, and has faced controversy over allegations of corruption and political interference.

The government of Prime Minister Hun Sen, himself a former Khmer Rouge fighter, has been accused of trying to protect the regime's former figures from facing justice.

AFP

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