Burundi’s conflict has, since the late 1980s, revolved around a struggle for power between the dominant Tutsi minority and the Hutu majority faction – which comprises 85% of the population. The violence has often involved the massacre and rape of civilians on a large scale, with more than 20,000 Hutus slaughtered in 1988 alone and approximately 200,000 people killed since. The assassination of a Hutu president in 1993, and the suspicious fatal airplane crash of another Hutu head of state the following year, led to renewed hostilities. The conflict has produced massive numbers of refugees, many of which have spilled spilled over into the Democratic Republic of the Congo. The Arusha Peace Agreement signed in 2000 and the Pretoria Protocol on Power Sharing in Burundi signed in 2003 were intended to lead to a peaceful resolution. However, the Hutu Forces Nationales de Libération (formerly known as Palipehutu-FNL) only agreed to a ceasefire in 2006. Electoral progress had been seen as encouraging, but allegations of vote-rigging and intimidation during national elections in 2010 have generated increasing insecurity amid reports of a nascent rebellion in the northwest.