Campaigners marched Monday in Nigeria's capital of Abuja during a silent protest to raise awareness about girls and boys abducted by Boko Haram. Sunday Alamba/AP hide caption

itoggle caption Sunday Alamba/AP

A man hammers a wall with elections posters at an open market in Kano, Nigeria, on Friday. The country is preparing for presidential elections on Saturday. President Goodluck Jonathan faces former military ruler Muhammadu Buhari and 13 other candidates in what is seen as the closest presidential race since the end of military rule in 1999. Goran Tomasevic/Reuters/Landov hide caption

itoggle caption Goran Tomasevic/Reuters/Landov

The most recent propaganda videos from Boko Haram have higher production values than in the past and other similarities to ISIS-produced videos. Boko Haram/Sendvid hide caption

itoggle caption Boko Haram/Sendvid