Elections were postponed from mid-February to allow the army to recapture territory from the Islamist militants of Boko Haram.

The two main candidates had pledged to prevent violence during and in the aftermath of the elections.

However, several hours after voting started, violent incidents at polling stations took place with many dead.

Militants from extremist group Boko Haram attacked several Nigerian towns, torching houses and fatally shooting those who fled before reportedly beheading some of the bodies with chainsaws. The string of terror attacks comes amid the presidential vote.