© The Associated Press/Extraordinary Chambers in the Courts of Cambodia/Nhet Sok HengFormer Khmer Rouge S-21 prison commander Kaing Guek Eav, also known as Duch, greets judges on his arrival in the courtroom for a session of U.N.-backed tribunal in Phnom Penh, Cambodia, as the court gives verdict on appeal filed by Duch against his conviction Friday, Feb. 3, 2012.
A U.N.-backed tribunal's Supreme Court lengthened the sentence for the Khmer Rouge's chief jailer to life imprisonment on Friday because of his "shocking and heinous" crimes against the Cambodian people.

The surprise ruling increased a lower court's 19-year sentence for Kaing Guek Eav, known as Duch. Prosecutors had appealed the sentence as too lenient, and outraged survivors had feared the man who oversaw the torture and killing of thousands could one day walk free.

Duch was the first defendant to be tried by the tribunal. He was commander of Phnom Penh's top-secret Tuol Sleng prison, code-named S-21. He admitted to overseeing the torture of his prisoners before sending them for execution at the "killing fields."

A coalition of 23 local civic groups, the Cambodian Human Rights Action Committee, welcomed Friday's decision and said Duch's victims had finally received justice.

In July 2010, the tribunal's lower court convicted Duch (pronounced DOIK) of war crimes, crimes against humanity, torture and murder.

He was sentenced to 35 years in prison but had 16 years shaved off for time served and other technicalities. The sentence was appealed both by prosecutors, who called for life imprisonment, and by Duch, who argued it was too harsh because he was merely following orders.

Judge Kong Srim, president of the Supreme Court Chamber, said Friday that the upper court felt the penalty should be more severe because the former jailer was responsible for the brutal deaths of so many.

"The crimes of Kaing Guek Eav were of a particularly shocking and heinous character based on the number of people who were proven to have been killed," the judge said. The tribunal says Duch oversaw the deaths of at least 12,272 victims but estimates have placed the number as high as 16,000.

The court said the high number of deaths and the extended period of time over which they occurred - from 1975 to 1979 - "undoubtedly place this case among the gravest before international criminal tribunals."

Duch, 69, stood calmly without emotion as the sentence was read. He then pressed his palms together and drew them to his chest in a show of respect to the judge, before being led away by court guards. The ruling is final with no other chance for appeal.

Andrew Cayley, the British co-prosecutor, said Duch can request a pardon after serving 20 years, or about seven years from now.

Duch trained, ordered and supervised his staff to conduct "systematic torture and execution of prisoners" and showed "dedication to refining the operations of S-21, which was the factory of death," the court said in a separate statement.

Prosecutors called the ruling a long-awaited victory.

"We can say that justice has now been served after more than 30 years," Chea Leang said. "To us and to the victims, this is a great success."

The tribunal is seeking justice for an estimated 1.7 million people who died from torture, starvation, exhaustion or lack of medical care during the Khmer Rouge's rule in the 1970s.

Three senior Khmer Rouge figures are currently on trial in what is known as Case 002. Unlike Duch, who admitted his role and asked for forgiveness, the others claim no wrongdoing.

They are 85-year-old Nuon Chea, the Khmer Rouge's chief ideologist and No. 2 leader; 80-year-old Khieu Samphan, an ex-head of state; and 86-year-old Ieng Sary, the former foreign minister. They are accused of crimes against humanity, genocide, religious persecution, homicide and torture.

In its ruling Friday, the court said Duch did not deserve a lighter sentence just because he was not a senior Khmer Rouge official, and there was no rule that reserves the highest penalties for those at the "top of the chain of command."

That position reflects a key area of contention involving possible future trials. Cambodian Prime Minister Hun Sen has insisted the tribunal should end its operations after the current trial of the three senior leaders.

Human rights groups and international prosecutors, however, favor an extension of the proceedings to a third and fourth trial, where defendants would be second-level Khmer Rouge officials suspected of heinous crimes.

The matter has not yet been settled and has led to tension between the tribunal and the Cambodian government.