2 former Khmer Rouge leaders appeal convictions at UN-backed tribunal

Cambodian villagers line up to enter a courtroom before the first appeal hearings against two former Khmer Rouge senior leaders, Khieu Samphan and Nuon Chea, at the U.N.-backed war crimes tribunal in Phnom Penh, Cambodia, Thursday, July 2, 2015. The two former Khmer Rouge leaders are facing charges of genocide, war crimes and crimes against humanity. (AP Photo/Heng Sinith) (The Associated Press)

Cambodian villagers wait to enter a courtroom before the first appeal hearings against two former Khmer Rouge senior leaders, Khieu Samphan and Nuon Chea, at the U.N.-backed war crimes tribunal in Phnom Penh, Cambodia, Thursday, July 2, 2015. The two former Khmer Rouge leaders are facing charges of genocide, war crimes and crimes against humanity. (AP Photo/Heng Sinith) (The Associated Press)

Cambodian villagers wait to enter a courtroom before the first appeal hearings against two former Khmer Rouge senior leaders, Khieu Samphan and Nuon Chea, at the U.N.-backed war crimes tribunal in Phnom Penh, Cambodia, Thursday, July 2, 2015. The two former Khmer Rouge leaders are facing charges of genocide, war crimes and crimes against humanity. (AP Photo/Heng Sinith) (The Associated Press)

Two leaders of Cambodia's former Khmer Rouge regime have appealed their convictions by a U.N.-backed tribunal that sentenced them to life in prison for their roles during the group's brutal rule in the 1970s.

Khieu Samphan, the Khmer Rouge's 83-year-old former head of state, and Nuon Chea, its 88-year-old chief ideologue, appeared in court Thursday.

The two men are the regime's only surviving senior leaders. In August, they were convicted of crimes against humanity in a ruling three and a half decades after the Khmer Rouge's 1975-1979 rule, which left an estimated 1.7 million people dead from starvation, disease and execution.

The tribunal said in a statement that the former leaders insisted they are innocent and filed hundreds of grounds for appeal.