25 years since the Rwandan genocide

In just 100 days in 1994, about 800,000 people were slaughtered in Rwanda by ethnic Hutu extremists. They were targeting members of the minority Tutsi community, as well as their political opponents, irrespective of their ethnic origin.

 How did the genocide start?

About 85% of Rwandans are Hutus but the Tutsi minority has long dominated the country. In 1959, the Hutus overthrew the Tutsi monarchy and tens of thousands of Tutsis fled to neighbouring countries, including Uganda.

 A group of Tutsi exiles formed a rebel group, the Rwandan Patriotic Front (RPF), which invaded Rwanda in 1990 and fighting continued until a 1993 peace deal was agreed. On the night of 6 April 1994 a plane carrying then-President Juvenal Habyarimana, and his counterpart Cyprien Ntaryamira of Burundi - both Hutus - was shot down, killing everyone on board.

Hutu extremists blamed the RPF and immediately started a well-organised campaign of slaughter. The RPF said the plane had been shot down by Hutus to provide an excuse for the genocide.

 How was the genocide carried out?

With meticulous organisation. Lists of government opponents were handed out to militias who went and killed them, along with all of their families. Neighbours killed neighbours and some husbands even killed their Tutsi wives, saying they would be killed if they refused. At the time, ID cards had people's ethnic group on them, so militias set up roadblocks where Tutsis were slaughtered, often with machetes which most Rwandans kept around the house.

 Why was it so vicious?

Rwanda has always been a tightly controlled society, organised like a pyramid from each district up to the top of government. The then-governing party, MRND, had a youth wing called the Interahamwe, which was turned into a militia to carry out the slaughter.

 How did it end?

The well-organised RPF, backed by Uganda's army, gradually seized more territory, until 4 July 1994, when its forces marched into the capital, Kigali. Some two million Hutus - both civilians and some of those involved in the genocide - then fled across the border into the Democratic Republic of Congo, at the time called Zaire, fearing revenge attacks. Others went to neighbouring Tanzania and Burundi.

Human rights groups say RPF fighters killed thousands of Hutu civilians as they took power - and more after they went into DR Congo to pursue the Interahamwe. The RPF denies this.