Habyarimana of Rwanda when their plane was shot down over Kigali on April 6. Ntibantunganya subsequently became president. Tutsi extremists continued to employ violence in the months after the coup to put pressure on FRODEBU. By mid-1994, the Tutsi-dominated army was conducting ethnic cleansing operations and UPRONA was pushing for constitutional revisions. Seeing no other options, FRODEBU leaders agreed to make concessions to their political opponents. This resulted in the signing of a protocole d'accord on 12 July, a power-sharing agreement which allotted 60 percent of all government and administration offices to FRODEBU and the rest to UPRONA. Unsatisfied, UPRONA and its allies increased their demands, leading to the signing of the Convention de Govournement in September. The agreement raised UPRONA's share of government positions to 45 percent, and mostly stripped the government and National Assembly of their powers by investing all executive authority in a National Security Council. The council comprised the president, prime minister, and eight other persons named by the president "on the proposition of political parties and after consulting with the representatives of civil society." A UPRONA/Tutsi faction then seized a majority on the council and effectively regained control of the country. Reyntjens described the convention as "the institutional translation of the October 1993 coup: the constitution [had] been shelved and the outcome of both the presidential and parliamentary elections swept aside as the president and parliament [were] placed under the tutelage of an unconstitutional body". Over the course of the 1994 negotiations, several FRODEBU leaders broke away from the talks and formed rebel groups, including the Conseil National Pour la Défense de la Démocratie-Forces pour la Défense de la Démocratie (CNDD-FDD), sparking the decade-long Burundian Civil War. Civil governance broke down as UPRONA and FRODEBU grew unable to cooperate, and on 25 July 1996 the army staged another coup which returned Buyoya to the presidency. Under regional pressure, the warring factions began negotiations in 1998. The Arusha Accords were signed in August 2000, but the agreement faced a troubled implementation process. Buyoya stepped down in 2003 and was replaced by Domitien Ndayizeye, while the CNDD-FDD ended its rebellion and engaged in the peace process. South African peacekeepers maintained order while a new consociational constitution was developed. While tensions remained high, political leaders engaged in more constructive and less inflammatory talks than in the aftermath of the 1993 coup, and the army withdrew itself from politics.