On 6 April 1994, Rwandan President Habyarimana's plane was shot down near Kigali Airport, killing both Habyarimana and the President of Burundi, Cyprien Ntaryamira, as well as their entourage and three French crew members. The attackers remain unknown. Prunier, in his 1995 book, concluded that it was most likely a coup d'état carried out by extreme Hutu members of Habyarimana's government who feared that the president was serious about honouring the Arusha agreement, and was a planned part of the genocide. This theory was disputed in 2006 by French judge Jean-Louis Bruguière, and in 2008 by Spanish judge Fernando Andreu. Both alleged that Kagame and the RPF were responsible. Rever also held Kagame responsible, giving as his motive a desire to plunge Rwanda into disorder and therefore provide a platform for the RPF to complete their invasion of the country. Evaluating the two arguments later in 2018, Caplan questioned the evidence used by Bruguière and Rever, stating that it has been repeatedly "discredited for its methodology and its dependence on sources who have split bitterly with Kagame". Caplan also noted that Hutu extemists had made multiple prior threats to kill Habyarimana in their journals and radio stations, and cited eyewitness accounts of roadblocks being erected in Kigali and killings initiated within one hour of the crash - evidence that the shooting of the plane was ordered as the initiation of the genocide.