(VOVworld) The supreme tribunal of the Extraordinary Chambers in the Courts of Cambodia (ECCC) on Friday ruled life sentence on a former Khmer Rouge leader. The 69-year old Kaing Guek Eav, called "Duch," was commander of the top secret Tuol Sleng prison code-named S-21 under the Khmer Rouge regime. In July 2010, the UN-protected ECCC lower court convicted Duch 35 years imprisonment on charges of war crimes, crimes against humanity, torture and the murder. However, the appeal ruling increased a lower ECCC court's sentence as prosecutors describe it as being too lenient. The Tuol Sleng prison headed by "Duch" from 1976 to 1979 was considered central to the security apparatus, detaining approximately 16,000 prisoners and most of them were executed. A large number of Cambodians, including hundreds of monks and survivors from the Khmer Rouge regime, attended the court hearing.