Citizens are going to the polls today after a last-minute postponement earlier this week.
The main challenger to reigning president Muhammadu Buhari is former Vice-President Atiku Abubakar.
It is not known exactly when the final results will be announced.
Experts say a winner could be declared as late as Tuesday.
Nigeria is Africa's most populated country.
Strong quake hits Mexican coast near Guatemala, triggers tsunami threat
A powerful magnitude 7.3 earthquake struck near the coast of Mexico's southernmost state of Chiapas on Friday, triggering a tsunami warning and shaking buildings in neighboring Guatemala and El Salvador.
US completes 'major' wave of strikes on Iran, Gulf states under attack
The US Central Command (CENTCOM) has announced that it completed its latest major wave of strikes against Iran, while Kuwaiti and Qatari defence forces reported intercepting missile attacks early on Friday.
Andy Burnham becomes UK Labour leader; next stop - prime minister
Andy Burnham, nicknamed the 'King of the North', was elected leader of Britain's governing Labour Party on Friday, the final step before becoming its seventh prime minister in a decade on a pledge to thwart the rise of the populist Reform UK.
Kuwait says Iranian attack damages power generation, water desalination station
One of Kuwait's power generation and water desalination stations was hit in an Iranian attack, causing damage to facilities, a fire and the disruption of a large number of electricity generation units, Kuwaiti authorities said on Friday.
One child injured in Iranian attacks on Qatar
Qatar's Ministry of Interior has announced that a child has sustained an injury as a result of falling debris from interception operations against Iranian attacks early on Friday.
