Two groups are sitting in circles in the grass in Simbi village, outside of Butare, Rwanda's second city. The men and women are counting money and talking, and they obviously know each other very well - it’s a friendly atmosphere. But 21 years ago, the scene wasn’t so idyllic. Rwanda marks the commemoration of the beginning of the genocide that killed some 800,000 Tutsis and moderate Hutus. People were killed by machete by extremist Hutus, but in many cases, by their own neighbors.