Chad's President, Mahamat Idriss Déby Itno, is calling for calm and urging hundreds of civilians who fled this week's Boko Haram attack that killed 24 soldiers in the volatile Lake Chad Basin to return to their villages. Meanwhile, Cameroon says it has reinforced its military presence around Lake Chad following the assault, which once again highlights the persistent security threat facing Cameroon, Chad, Nigeria, and Niger despite years of joint military operations against extremist groups. Moki Edwin Kindzeka reports from Yaounde, Cameroon...