Nigeria's Buhari re-elected as president

Nigerian President Muhammadu Buhari has been re-elected for a second four-year term, Nigeria's Independent National Electoral Commission (INEC) announced Wednesday. 

In an election marred by delays and violence, the 76-year-old has defeated his rival former Vice President Atiku Abubakar, with a margin of just under four million votes, CGTN reports. 

Buhari, the candidate of the governing All Progressives Congress (APC) party, topped the poll with 15,191,847, or 55.6 percent of the total 27,324,583 valid votes in presidential election held on Saturday, announced Mahmood Yakubu, chairman of the Independent National Electoral Commission (INEC).

The runner-up was Abubakar Atiku of the main opposition People's Democratic Party (PDP), who won 11,262,978, or 41.2 percent of the valid votes.

Addressing supporters at his All Progressives Congress (APC) party campaign headquarters, Buhari said his administration will intensify efforts to improve security and bolster the economy.

He also said he was "deeply humbled" to have secured a second term.

Before the vote, a militant group in Nigeria's oil-rich southern Niger Delta threatened to cripple the economy if Buhari was re-elected.

The militant group was believed to be behind a 2016 wave of violence, including attacks on pipelines and other facilities, that helped push Nigeria into recession.