Nigerian President Muhammadu Buhari has secured a second term as the leader of Africa's most populous country, the electoral commission said Wednesday, after a delayed election and opposition claims the vote was rigged.

The former military dictator won by more than 4 million votes, beating his main rival Atiku Abubakar, a former vice president. 

Buhari secured 15.1 million votes, while Abubakar of the People's Democratic Party (PDP) received 11.2 million. Voter turnout was a meagre 35.6 percent. 

To win, a candidate needed a simple majority of votes nationwide and at least 25 percent support in two-thirds of Nigeria's 36 states and the capital territory.

Supporters of Buhari's All Progressives Congress (APC) celebrated the victory in the capital, Abuja.

Opposition claims fraud

On Tuesday, the PDP demanded a halt to vote counting from Saturday's election, citing electoral fraud.

Tanimu Turaki, a spokesman for the PDP, said handheld electronic machines that check biometric voter identity cards had been tampered with, leading him to call for an "immediate halt to the ongoing collation of results."

Read more: Nigeria: Dozens dead in election violence

Turaki said the number of accredited voters in the northeastern state of Yobe, won by Buhari, had exceeded the number of votes cast.

"The PDP predicates this demand on available evidence to the effect that data from the card readers are being reconfigured to suit the manipulations" of the ruling party, he said.

He also said there was "credible information" that the election in neighboring Borno state was a "figure-writing exercise" done according to the "whims and caprices" of the APC.

Buhari's party has accused the opposition of manipulating the results and demanded they provide evidence of election fraud. 

Delays, violence challenge confidence

Saturday's vote was marked by delays, logistical problems and violence, casting a shadow over the credibility of the results.

Read more: Elections in Nigeria: Smartphone, truth and lies

The Economic Community of West African States, the African Union and the United Nations have urged all sides to await official results before filing electoral complaints. It is unclear if Abubakar will challenge the results. 

cw, aw/cmk (AP, AFP, Reuters)

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