Cameroonian President Paul Biya(C, front) attends the extraordinary summit in Yaounde, Cameroon on Feb. 16, 2015. The leaders of Economic Community of Central African States (ECCAS) agreed Monday in an extraordinary summit to provide Cameroon and Chad with an emergency aid of 50 billion FCFA (about 100 million U.S. dollars) to combat Boko Haram. (Xinhua/Fabrice Ngon)