December accord, mediated by President Omar Bongo of Gabon, called for follow-on, inclusive political negotiations between the government and the opposition. Sassou's second presidency Sassou won elections in 2002 with an implausible 90% or so of the votes. His two main rivals, Lissouba and Bernard Kolelas, were prevented from competing and the only remaining credible rival, André Milongo, boycotted the elections and withdrew from the race due to, among other reasons, perceived voter fraud on the part of Sassou. A new constitution was agreed upon in January 2002, granting the president new powers and extending his term to seven years as well as introducing a new bicameral assembly. On December 30, twenty opposition political parties issued a statement through spokesman Chistope Ngokaka, saying Sassou's government had purchased "weapons and military craft... under contracts signed between the officials in Brazzaville and the government in Beijing." Sassou was re-elected for a further seven-year term at the next presidential election in July 2009. In 2015, Sassou changed the constitution to run in the 2016 election. He won the election believed by many to be fraudulent. After violent protests in the capital, Sassou attacked the Pool region, where the Ninja rebels of the civil war used to be based, in what was believed to be a distraction. This led to a revival of the Ninja rebels who launched attacks against the army in April 2016, leading 80,000 people to flee their homes. A ceasefire deal was signed in December 2017. See also History of Africa People's Republic of the Congo Politics of the Republic of the Congo List of heads of government of the Republic of the Congo List of heads of state of the Republic of the Congo Brazzaville history and timeline Notes Bibliography . . . . . . Petringa, Maria: Brazza, A Life for Africa. Bloomington, Indiana: AuthorHouse, 2006. Wm. Roger Louis and Jean Stengers: E.D. Morel's History of the Congo Reform Movement, Clarendon Press Oxford, 1968. Middle Congo (colonial) Republic of the Congo