The UN-backed Cambodia tribunal sentenced a senior member of the Khmer Rouge to 35 years in prison on Monday in its first verdict three decades after the Maoist "Killing Fields" revolution tore Cambodia apart.

Also read: “He’s killed many people; why does he only get 19 years?”

Judges at the Extraordinary Chambers in the Courts of Cambodia (ECCC) found Kaing Guek Eav - better known by his nom de guerre, “Duch” - guilty of crimes against humanity and war crimes for running the S 21 - or Tuol Sleng - prison, a converted school that symbolizes the horrors of the ultra-communist regime that killed over 1.7 million Cambodians in 1975-79.

He was convicted of religious political persecution, extermination, imprisonment, torture perpetrated against at least 12,272 victims (full judgement). But the 67-year-old the former schoolteacher only has 19 years left to serve because the judges reduced his sentence by 16 years, giving him credit for time served as well as his illegal detention in a Cambodian military prison before he was handed over to the tribunal. 

The verdict was short of the maximum 40 years sought by the prosecution and of the life behind bars demanded by many Cambodians who have struggled to find closure for one of the darkest chapters of the 20th century.

Duch, the first person to stand trial before the ECCC, served as Deputy and then Chairman of S-21, the notorious security centre tasked with interrogating and executing persons perceived as enemies of Democratic Kampuchea by the Communist Party of Kampuchea. S-21 was run between 1975 and 1979.

The ECCC judges found that "every individual detained within the prison was "destined for execution in accordance with the Communist Party of Kampuchea police to “smash” all enemies. In addition to mass executions, many detainees died as a result of torture and their conditions of detention."

Although finding a minimum of 12,272 individuals to have been detained and executed at S-21 on the basis of prisoner lists, the chamber indicated that the actual number of detainees is likely to have been considerably greater.

Duch admitted to overseeing the torture and killing in his prison, but has said he was only carrying out orders. Now a born-again Christian, he has also expressed "excruciating remorse" for the S-21 victims, most of them tortured and forced to confess to spying and other crimes before they were bludgeoned at the "Killing Fields" execution sites during the agrarian revolution, which ended with a 1979 invasion by Vietnam.

Duch's 72-day trial started on 30 March 2009. It heard 24 witnesses, 22 Civil Parties and nine experts, while more than 28,000 people followed  the proceedings from the public gallery.

Duch is the first person to be sentenced by an international criminal court for the atrocities committed by the Khmer Rourge regime 30 years ago. The tribunal is holding four other Khmer Rouge leaders, with the second trial scheduled to start next year.

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• First Khmer Rouge prison survivor testifies
• Cambodia genocide trial ready to start
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