LAKE KIVU, Rwanda — In the evening, the green leaves of the verdant hills of Lake Kivu turned black against the orange sky, and a calm settled across the water. And then, out of the silence, came a ...

Claude Muhayimana, now 65, worked as a chauffeur at a hotel in Kibuye, on the banks of Lake Kivu, western Rwanda at the time of the genocide of more than 800,000 Rwandans, mainly Tutsis.