The war began on 1 October 1990 when the RPF invaded north-eastern Rwanda, advancing into the country. They suffered a major setback when Rwigyema was killed in action on the second day. The Rwandan Army, assisted by troops from France, gained the upper hand and the RPF were largely defeated by the end of October. Kagame, who had been in the United States during the invasion, returned to take command. He withdrew troops to the Virunga Mountains for several months before attacking again. The RPF began a guerrilla war, which continued until mid-1992 with neither side able to gain the upper hand. A series of protests forced Rwandan President Juvénal Habyarimana to begin peace negotiations with the RPF and domestic opposition parties. Despite disruption and killings by Hutu Power, a group of extremists opposed to any deal, and a fresh RPF offensive in early 1993, the negotiations were successfully concluded with the signing of the Arusha Accords in August 1993.