Rwanda: Haunted Nation
A good man in Rwanda
Death of an exile
Will Hutus return?
Hundreds of people have attended a Mass in the Rwandan capital ahead of a week of official mourning to mark the 20th anniversary of the country's genocide.
But a diplomatic row has seen France pull out of the commemorative events.
The Mass at Sainte-Famille Catholic church in Kigali remembered those who died in the church itself or elsewhere in the country.
At least 800,000 people - mostly ethnic Tutsis and moderate Hutus - died at the hands of Hutu extremists in 1994.
Most of the victims of the genocide were attacked with machetes during 100 days of slaughter that began on 6 April 1994, shortly after Hutu President Juvenal Habyarimana was killed when his plane was shot down over the Rwandan capital.
Some Christian leaders were implicated in the violence.
BBC Africa's Kassim Kayira explains the events that shook Rwanda in 1994
A genocide survivor who attended the Mass, Innocent Muhozi, said: "Today's Mass was about resurrection and I believe that one day, the souls of the people we lost will resurrect.
"This church has a very long history because many people died in it during genocide but some also survived it because they were in this church."
Pope Francis, in his weekly address to the faithful at St Peter's Square in the Vatican, spoke of the anniversary.
"On this occasion I would like to express my paternal closeness to the people of Rwanda, encouraging them to continue with determination and hope, the process of reconciliation that has already manifested its fruits, and the commitment of human and spiritual reconstruction of the country," the head of the Catholic Church said.
The killings in Rwanda ended in July 1994 when the Rwandan Patriotic Front (RPF), a Tutsi-led rebel movement that entered the country from from Uganda, marched on Kigali and seized control of the country.
France pulls out
The French government announced it was pulling out of the 20th anniversary commemorations following an accusation by Rwandan President Paul Kagame - who led the RPF to victory - that France had participated in the mass killings.
Kagame reportedly said France had a "direct role" in the "political preparation for genocide"
In an interview with the French-language weekly news magazine Jeune Afrique, Mr Kagame denounced the "direct role of Belgium and France in the political preparation for the genocide".
French Justice Minister Christiane Taubira cancelled her plans to attend the events in Kigali on Monday following the remarks.
The French foreign ministry said Mr Kagame's comments went against reconciliation efforts between the two countries.
Rwanda responded by accusing the French government of overreacting.
"For our two countries to really start getting along, we will have to face the truth. The truth is difficult, the truth of being close to anybody who is associated with genocide understandably is a very difficult truth to accept," Rwandan Foreign Minister Louise Mushikiwabo said.
Mr Kagame's party still controls the government and has long accused France - an ally of Mr Habyarimana's government at the time - of aiding the genocide.
Rwanda's government has long accused France - an ally of the previous regime - of aiding the genocide
In recent years there has been a thaw in relations between the two countries, with a visit by Mr Kagame to Paris in 2011 and the establishment by France of a genocide investigation unit.
Last month, a Paris court sentenced former Rwandan spy chief Pascal Simbikangwa to 25 years in jail for his role in the genocide - the first such conviction in France.
France has acknowledged that serious errors were made during the genocide in Rwanda.
A Rwandan commission in 2008 said France was aware of preparations for the genocide and helped train ethnic Hutu militias who participated in killings.
Paris said its forces had helped protect civilians as part of a UN-mandated intervention in Rwanda. But Mr Kagame said French troops had protected the militias carrying out the killings.