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.
One attacker killed, two wounded in gunfight near Israeli consulate in Istanbul
One attacker was killed and two others were wounded in a gunfight with police near the Israeli consulate in Istanbul on Tuesday, the city’s governor said, adding that two police officers were slightly wounded.
French high speed train crashes into military truck, killing driver
A French high-speed train has crashed into a truck carrying military equipment at a level crossing near Calais on Tuesday morning, killing the train driver, a spokesperson for the local prefecture said.
Israeli military tells people in Iran to avoid using trains
The Israeli military on Tuesday has told people in Iran not to use trains or go near railway lines.
Three killed after Russian drone hits city bus in Ukraine's Dnipro region
A Russian drone strike on a city bus has killed three people and injured 12 more on Tuesday in the city of Nikopol in the eastern Dnipropetrovsk region, Ukrainian officials said.
Malaysian ship secures safe transit through Hormuz
A Malaysian vessel has secured safe transit through the Strait of Hormuz and is currently proceeding to its final destination, Malaysia's foreign ministry said on Tuesday.
