Cambodia's U.N.-backed genocide tribunal has indicted the four top surviving leaders of the Khmer Rouge regime, from left to right, Nuon Chea, 84, the group's ideologist; former head of state and public face of the regime, Khieu Samphan, 79; former Foreign Minister Ieng Sary; and his wife Ieng Thirith, ex-minister for social affairs, both in their 80, for 1.7 million deaths in the 1970s. (AP Photo/Heng Sinith/Chor Sokunthea, File)