PHNOM PENH, Cambodia, Feb. 3 (UPI) -- A U.N.-backed genocide tribunal trying Cambodia's Khmer Rouge leaders increased the sentence of the brutal regime's prison chief to life imprisonment.
The tribunal's highest judiciary chamber rejected a petition for Kang Guek Eav, also known as Duch, appealing his 35-year prison term imposed in 2010, and raised it to a life sentence, Friday, the Phnom Penh Post reported.
Duch, now 69, was accused of running the notorious S-21 "factory of death" detention facility. Up to 15,000 of the inmates were reportedly tortured and later executed in Cambodia's "killing fields."
They were among an estimated 2 million people who died during the Khmer Rouge's rule from 1975 to 1979.
"In the Supreme Court chamber's view, [Duch's] leadership role and particular enthusiasm in the commission of his crimes are aggravating factors that should be given significant weight in the determination of his sentence," chamber President Kong Srim read from a summary of the judgment.
The ruling said the "particularly shocking and heinous character" of Duch's crimes over an "extended period of time … undoubtedly place this case among the gravest before international criminal tribunals," the Post reported.
In rejecting his appeal, the chamber said undue weight had been given by the trial court in 2010 to factors such as Duch's expressions of remorse and cooperation.
Duch listened attentively to the higher chamber's ruling, bowed his head and raised both his hands in a prayer, the Post said.
In appealing his original sentence, Duch said he was a low-ranking official who merely followed orders while fearing for his own life, the Financial Times reported. The prosecution had sought a longer sentence.
Critics, including those with the Association of Khmer Rouge Victims, said the higher chamber's decision against Duch should not make him a scapegoat for all the atrocities committed by the Khmer Rouge government, the Times reported.
Other surviving Khmer Rouge leaders on trial are Nuon Chea, Khieu Samphan and Ieng Sary, all reported to be in their 80s. Ieng Thirith, 79, the regime's social affairs minister and the wife of Ieng Sary, was ruled unfit to stand trial and was ordered released.
The tribunal was set up in 2003 by the United Nations and the Cambodian government as an independent court.