Former Khmer Rouge leader Nuon Chea at an ECCC trial in Phnom Penh in 2008. (Photo: AFP)

Neth Pheaktra, a spokesman for the Extraordinary Chambers in the Courts of Cambodia (ECCC), commonly known as the United Nations-backed Khmer Rouge tribunal, confirmed that Nuon Chea died at the Khmer Soviet Friendship hospital.

Nuon Chea was transferred from the ECCC's detention center to the hospital for medical treatment since last month. He was arrested in 2007 and was sentenced life imprisonment last year for genocide, crimes against humanity and grave breaches of the 1949 Geneva Conventions.