The first massacres in Rwanda took place in 1959. Thereafter, almost in a regular manner, killings of the Batutsi became a common practice. In the 1960s, 1970s, 1980s and early 1990s massacres of Batutsi were common. Between April and July 1994, over 1 million Rwandese people, mainly Batutsi and some Bahutu opposition were killed by the genocidal regime. Many people were involved in the killings. Those who planned and organised the genocide include the late President, Major General Juvenal Habyarimana, top government officials, including members of the so-called Provisional Government, the Presidential Guard, the National Gendarmerie, the Rwanda Armed Forces (FAR), the MRND-CDR militia (Interahamwe), local officials, and many Bahutu in the general population.
Preparation to carry out genocide by these groups involved the training of the militia, the arming of both the militia and some sections of the population, the establishment and widespread use of a hate radio called Radio television libre de mille collines (RTLM), and the distribution of lists of those targeted fro elimination. Repeatedly, these groups prevented the establishment of the Arusha Peace Accords.
When the genocide began, the United Nations had a peacekeeping force - the United Nations Assistance Mission for Rwanda (UNAMIR) - in Rwanda of about 2500 troops. The first reaction of the United Nations, and indeed of other nations that had their own nationals in Rwanda, was to withdraw their troops and their nationals respectively. Under the circumstances the RPF had to fight again in order to stop the genocide.