Nigerian voters prepare to go to polls
Nigerians are about to go to the polls to elect a president, with incumbent Goodluck Jonathan facing a strong challenge from Muhammadu Buhari. It is expected to be the most closely fought election since independence, set against a background of violence from militant Islamist group Boko Haram. The People's Democratic Party (PDP) has dominated Nigerian politics since 1999, but the All Progressives Congress (APC) is viewed as a serious challenge.
