Visitors walk past a mass grave site at the Kigali Genocide Memorial Centre, as the country prepares to commemorate the twentieth anniversary of the 1994 genocide in the Rwandan capital Kigali April 5, 2014. An estimated 800,000 people were killed in 100 days during this genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS)