The tribunal's five-judge panel seeks justice for Cambodians who suffered under the Khmer Rouge regime. A quarter of Cambodia's population perished from execution, overwork and torture. It was one of the darkest chapters of the 20th century.

Duch's trial is the first of many to come.

The 72 day trial has had witnesses speak of beatings, electrocution, near starvation and other terrors at S-21 prison run by Duch. Now 66, he is accused of "crimes against humanity, enslavement, torture, sexual abuses and other inhumane acts".

Only seven of those held at S-21 survived.

Most Cambodians want swift justice for Duch.

[In Soy, Khmer Rouge Persecution Survivor]
"I want to see how much the court punishes him, because I suffered so much during that regime."

Many have applauded the motives of the tribunal, which has asked international donors for a $143 million budget to run until 2010. Court officials say that the verdict against Duch is expected to be handed down early next year.

Duch has expressed remorse for the S-21 victims. Most of them tortured and forced to confess to spying and other crimes… before they were bludgeoned to death in the country's "Killing Fields" execution sites.

But he denies personally killing or torturing prisoners and said he was following orders in fear for his own life. He faces up to life in prison if convicted.

Four other senior Khmer Rouge cadres are in custody awaiting trial.