After the fall of the Khmer Rouge, Duch disappeared for two decades before he was located in north-west Cambodia by a British journalist in 1999, and then arrested. Others facing trial are Khieu Samphan, the Khmer Rouge's former head of state; Ieng Sary, its foreign minister; his wife Ieng Thirith, who was minister for social affairs; and Nuon Chea, the movement's chief ideologue.