Four top Khmer Rouge leaders went on trial at Cambodia's UN-backed war crimes court on Monday charged with genocide and other atrocities during the Maoist group's reign of terror in the late 1970s. The case, described as the most complex since the landmark Nazi trials after World War II, has been long awaited by survivors of the regime, which wiped out nearly a quarter of the population. A natural sound version of an AFPTV report.