By Felix Onuah and Camillus Eboh

ABUJA (Reuters) -Nigeria’s new president-elect, Bola Tinubu, defended the election he just won as credible on Wednesday but Peter Obi, one of his main opponents, planned to challenge the result in court, according to Obi’s running mate.

The main opposition parties have described the outcome of Saturday’s election as fraudulent after new technology that the electoral commission had promised would make the process more transparent instead malfunctioned, eroding trust.

Voter turnout was also low, even by Nigerian standards. With total votes cast at just under 25 million, out of 87 million people with voter identity cards and eligible to vote, turnout was only 29%. The 2019 election saw a 35% turnout.

“I am very happy I have been elected the president of the federal republic of Nigeria,” Tinubu, 70, who was the ruling party’s candidate, said to cheers in the federal capital Abuja. “This is a serious mandate. I hereby accept it.”

A former governor of Lagos and a veteran power broker at the heart of Nigeria’s political class, Tinubu will take the helm of Africa’s most populous country, biggest economy and top oil producer as it struggles with overlapping crises.

Those include Islamist insurgencies in the northeast, an epidemic of kidnappings for ransom and conflicts between herders and farmers, as well as shortages of cash and fuel, industrial-scale oil theft, high inflation and deep-rooted poverty.

But for now, the focus is on the election itself, in which Tinubu won 37% of the vote, or 8.79 million votes, according to official results announced by the Independent National Electoral Commission (INEC). Nigeria has a population of over 200 million.

“I commend INEC for running a credible election no matter what anybody says,” said Tinubu. “The lapses that were reported, they were relatively few in number and were immaterial to affect the final outcome of the election.”

‘DISAPPOINTING’

But Yusuf Datti Baba-Ahmed, Obi’s running mate, said a legal challenge was already being mounted. “We will go to court within the limit of the time. The legal people are putting the papers together,” he said, calling on supporters to remain peaceful.

Nigeria has a long history of political violence, but the atmosphere was calm in the main cities on Wednesday, with many people appearing deflated.

“In the eyes of God, the man (Tinubu) is not the winner,” trader Mercy Efong said in Awka, in Obi’s home state of Anambra.

Nigeria Civil Society Situation Room, a group that monitored the election, said the outcome was not credible because of what it described as severe logistical failures, a lack of transparency, disruption of voting and violent incidents.

“This is all the more disappointing since the elections were held in an atmosphere in which the people showed remarkable commitment to democracy, eagerly engaging in the electoral process and waiting patiently to vote in very difficult circumstances,” the group said in a statement.

Some voters were unable to cast their ballots due to malfunctioning of voter card reading machines.

INEC said the main opposition challenger, former vice president and political veteran Atiku Abubakar, won 29%, or 6.98 million votes, while outsider Obi won 25%, or 6.1 million votes.

To win, a candidate must get more votes than the others and at least 25% of the ballot in at least two-thirds of Nigeria’s 36 states. Tinubu cleared both hurdles.

‘EVERYTHING UPSIDE DOWN’

Obi’s slick social media campaign had generated fervent support among younger, more educated urban voters hoping for an end to the duopoly of Tinubu and Atiku’s parties, which have alternated in power since the end of army rule in 1999.

Remarkably, Obi, an ethnic Igbo, won in Lagos, which was considered Tinubu’s political stronghold and is in the heartland of the president-elect’s Yoruba ethnic group. The vast metropolis is Nigeria’s commercial hub and most dynamic centre.

Outgoing President Muhammadu Buhari congratulated his successor. “Elected by the people, he is the best person for the job. I shall now work with him and his team to ensure an orderly handover of power,” Buhari said in a statement.

INEC’s vaunted new technology, an electronic system that was supposed to identify voters using biometric data and transmit results directly from polling stations to a secure portal, seemed to overwhelm Nigeria’s patchy telecoms network.

This meant results had to be collated manually inside ward and local government counting centres as in previous elections, giving rise to suspicions that the numbers were being manipulated.

“President Buhari said that he would do a free and fair election (but) INEC is now turning everything upside down,” said rickshaw driver Nedu Chukwunata.

As Lagos governor from 1999 to 2007, Tinubu won praise for partially fixing some of the city’s problems, including reducing violent crime, improving waste collection and easing traffic.

Tinubu, however, sometimes appeared frail in public, slurring his speech, answering questions with platitudes and skipping several campaign events, leaving some to doubt how effective or dynamic he will be as leader.

(Additional reporting by Ahmed Kingimi in Maiduguri, Hamza Ibrahim in Kano, MacDonald Dzirutwe and Tim Cocks in Lagos; Writing by Tim Cocks and Estelle Shirbon; Editing by Alex Richardson)

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