Two top leaders of Cambodia's Khmer Rouge regime were found guilty of genocide on Friday, in a landmark ruling almost 40 years after the fall of a brutal regime that presided over the deaths of a quarter of the population.

The Khmer Rouge's former head of state Khieu Samphan, 87, and "Brother Number 2" Nuon Chea, 92, are the two most senior living members of the ultra-Maoist group that seized control of Cambodia from 1975-1979. The reign of terror led by "Brother Number 1" Pol Pot left some two million Cambodians dead from overwork, starvation and mass executions but Friday's ruling was the first to acknowledge a genocide.