Jean de Dieu Kamuhanda was born on 3 March 1953 in Gikomero in the Prefecture of Kigali-Rural, Rwanda. On 25 May 1994, he was appointed to the position of Minister for Higher Education, Scientific Research and Culture in the interim government, replacing Dr. Daniel Nbangura in this post. He held this position until mid-July 1994.
Kamuhanda played a leading role in the systematic extermination of the Tutsis who had taken refuge in the parish and the school in Gikomero in the Prefecture of Kigali-Rural, Rwanda in 1994.
Between the 6 and 10 April 1994, at a gathering which took place at the home of one of his cousins in Gikomero, Kamuhanda was said to have addressed those present to draw their attention to the fact that the massacres against the Tutsis in the Gikomero Commune had not yet been started. He was said to have provoked them into committing these massacres, adding that he would furnish the arms to those present in order that they might begin to commit the slaughter. At the end of this meeting, he was reported to have personally handed out firearms, hand grenades and machetes and told those present that they in turn should redistribute these arms to other persons. He was said to have stressed the fact that he would return later to check on whether the massacres had indeed begun.
After the start of the massacres against the Tutsis in Rwanda in April 1994, a large number of Tutsi civilians from the Prefecture of Kigali-Rural took refuge in the protestant parish of Gikomero and in its adjacent school. On 12 April 1994, Kamuhanda was reported to have set in motion the attack against the Tutsis who had sought refuge there, by leading a group of armed men to the parish, arriving at the parish in the early afternoon, accompanied by the Interahamwe (extremist Hutu militia) , policemen, soldiers and civilians, who were all under his authority. He was then said to have given the command to start the killings. As soon as the killings were underway, Kamuhanda reportedly left the neighbourhood. A great number of Tutsis were killed during this attack.
Confronted with the advance of the troops of the RPF (Rwandan Patriotic Front – an opposition movement composed essentially of Tutsi refugees and led by Paul Kagame) Kamuhanda fled Rwanda. On 26 November 1999, he was arrested in a hostel belonging to the town of Bourges, in France.