Rwanda girls light each other's candles during a night vigil for the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Rwandan President Paul Kagame kicks off the night vigil by lighting a candle during the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Rwandan people hold candles in a night vigil for the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

People follow the proceedings of the 20th anniversary commemoration of the Rwandan genocide, in Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY POLITICS CIVIL UNREST) 

Rwandan President Paul Kagame is shown on big screen as he delivers his speech during the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Rwandan President Paul Kagame delivers his speech during the commemoration of the 20th anniversary of the Rwandan genocide, in Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Kenya's President Uhuru Kenyatta (L) and United Nations Secretary General Ban Ki-moon attend a wreath-laying ceremony at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Uganda's President Yoweri Museveni attends a wreath-laying ceremony at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Rwandan President Paul Kagame and his wife Jeannette Kagame attend a laying of the wreath ceremony at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Somali President Hassan Sheikh Mohamud (L) and his Kenyan counterpart Uhuru Kenyatta attend a wreath-laying ceremony at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Rwandan President Paul Kagame (L) and the United Nations Secretary General Ban Ki-moon leave after a wreath-laying ceremony at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

South Sudan's President Salva Kiir attends a wreath-laying ceremony at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

United Nations Secretary General Ban Ki-moon (5th L), Rwandan President Paul Kagame (2nd L), his wife Jeannette Kagame and the African Union Commission Chairperson Nkosazana Dlamini Zuma (6th L) light the flame, as they participate in the commemoration of the 20th anniversary of the Rwanda Genocide in Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

British Foreign Secretary William Hague (R) waits with other dignitaries to lay wreaths at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Former President of Ireland Mary Robinson (L) and former President of Burundi Pierre Buyoya with his wife Sophie arrives at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the genocide in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Former British Prime Minister Tony Blair and former South African President Thabo Mbeki (R) arrive at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the Rwandan genocide in Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

African Union Commission Chairperson Nkosazana Dlamini Zuma arrives at the Kigali Genocide Memorial Centre during the commemoration of the 20th anniversary of the genocide in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

South Sudan's President Salva Kiir leaves with other dignitaries at the end the commemoration of the 20th anniversary of the genocide, in the Rwandan capital Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY CIVIL UNREST POLITICS) 

Rwandan President Paul Kagame (R) and his Ugandan counterpart Yoweri Museveni follow the proceedings of the 20th anniversary commemoration of the Rwandan genocide, in Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY POLITICS CIVIL UNREST) 

Children take part in the proceedings of the 20th anniversary commemoration of the Rwandan genocide, in Kigali April 7, 2014. An estimated 800,000 people were killed in 100 days during the genocide. REUTERS/Noor Khamis (RWANDA - Tags: ANNIVERSARY POLITICS CIVIL UNREST)