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.
Iran says peace talks would be 'unreasonable' following Israeli strikes
Iran's lead negotiator, parliament speaker Mohammed Bager Qalibaf, has suggested it would be "unreasonable" to proceed with talks to forge a permanent peace deal with the US after Israel pounded Lebanon with its heaviest strikes yet on Wednesday, killing hundreds.
Vance to lead US delegation to Iran talks on Saturday
US President Donald Trump is dispatching his Iran negotiating team, led by Vice President JD Vance, to Pakistan for talks, the White House told reporters on Wednesday, adding that the first round of negotiations would take place on Saturday.
Trump criticises NATO over Iran in meeting with alliance's boss
US President Donald Trump vented his frustration with NATO during a private meeting with its secretary-general, Mark Rutte, on Wednesday as relations in the military alliance reached a crisis point over the Iran war.
Bahrain airport begins gradual flight resumption
The operator of Bahrain International Airport, Bahrain Airport Company, has confirmed the gradual resumption of flights following the reopening of the Kingdom’s airspace.
Israeli strikes pummel Lebanon, killing 250 in deadliest day of war
Israel has carried out its heaviest strikes on Lebanon since the conflict with Hezbollah broke out last month, killing more than 250 people on Wednesday, as the group resumed rocket attacks on northern Israel after a brief pause under the two-week US-Iran ceasefire.
