Bola Tinubu of the governing APC party has won the central state of Kogi, garnering 240,751 votes, according to Nigeria's electoral commission.
It is a comfortable victory over Atiku Abubakar of opposition PDP, who came second with 145,104 votes.
Peter Obi of Labour Party registered 56,217 ballots.
Image source, AFPThe Ooni of Ife's kingdom is in present-day Osun state.
A revered monarch in south-west Nigeria has appealed for all politicians and the electoral commission not to inflame tensions as results from Saturday’s presidential election are announced.
The Ooni of Ife, Adeyeye Enitan Ogunwusi, called for them to conduct themselves in a mature manner “in order for peace to reign”.
The governing APC party’s candidate Bola Tinubu is currently leading the vote, while the opposition PDP and Labour Party have called for a fresh election, alleging malpractices by the Independent National Electoral Commission (Inec).
The king, who is also co-chairman of National Council of Traditional Rulers of Nigeria, urged Nigerians to be patient as they await the result.
The Ooni of Ife's kingdom is in present-day Osun state.
"Nigerians have suffered enough and any form of uproar will add to the already harsh condition of living for Nigerians especially the poor and vulnerable amongst us," the Ooni said in a statement released by his palace.
"I equally urge our youths to resist all pressure to be utilised by unpatriotic elements as thugs."
The southern state of Abia has voted overwhelmingly for Labour Party presidential candidate Peter Obi, according to official results currently being announced at the national collation centre in the capital, Abuja.
Mr Obi got 327,095 votes.
Atiku Abubakar of the opposition PDP was a distant second with 22,676. Bola Tinubu, the candidate for ruling APC party, got 8,914.
Peter Obi, the presidential candidate of Labour Party, has registered a huge win in the southern Edo state, according to official results.
Mr Obi got 331,163 his closest rival Bola Tinubu of the governing APC garnered 144,471.
The PDP's Atiku Abubakar, who has served two terms as the country's vice-president, got 89,585 in the state.
The main opposition presidential candidate Atiku Abubakar of the PDP has won the southern oil-rich state of Akwa Ibom.
He garnered 214,012 followed by APC's Bola Tinubu, who got 160,620.
Labour Party's Peter Obi got 132,683.
The total votes cast were 587,417 of these 32,328 votes were rejected.
The BBC's Yemisi Adegoke has been following Nigeria's election in the Adamawa State.
Read MoreThree parties are demanding fresh presidential elections, alleging widespread irregularities.
Read MorePeter Obi, presidential candidate for the opposition Labour Party, has won the capital, Abuja, with a landslide.
He gained 281,717 votes compared to 90,902 won by his nearest rival, Bola Tinubu of the ruling APC.
The PDP’s Atiku Abubakar took 74,194 votes.
Mr Obi is popular with young voters in urban centres and has also won Lagos state.
His party and the PDP have called for fresh election, alleging irregularities.
Mr Tinubu is leading in the vote so far.
Bola Tinubu, the presidential candidate for the governing APC party, has won the vote in Benue state in central Nigeria, official results from the electoral commission say.
He gained 310,468 votes, just ahead of the Labour Party’s Peter Obi, who got 308,372 ballots.
According to the results, 27,687 votes in the state were rejected.
Atiku Abubakar, of the main opposition PDP, came third with 130,081 votes.
Bola Tinubu, the presidential candidate for the ruling APC party, has won Niger state, west of the capital Abuja, the electoral commission has announced.
He garnered 375,183 votes, followed by Atiku Abubakar of the opposition PDP, who got 284,898.
Peter Obi of the Labour Party came fourth behind Rabiu Kwankwaso of NNPP.
Niger is the 17th of 36 states to be declared.
Joshua Ajayi
BBC News, Abuja
Proceedings are getting under way at the national collation centre in the capital, Abuja.
The results from 17 states are now ready to be announced, the Independent National Electoral Commission (Inec) says.
First some people are addressing the Inec chairman.
The chairman of the Inter-party Advisory Committee (Ipac), Yabani Sani, asked for him to continue announcing results, despite a call by some opposition parties for fresh elections.
“The show must go on,” he said.
Daniel Nwanyanwu, candidate for the small Zenith Labour Party (ZLP), is backing this position.
Chiagozie Nwonwu
BBC News
Instead of uploading a photo of presidential election results at a ward level to Nigeria’s electoral commission website, the BBC has confirmed that there have been occasions when mugshots of people appear to have been mistakenly posted.
The BBC’s team tracking misinformation about the poll investigated two cases highlighted on social media.
In one widely shared video someone navigates the portal of the Independent National Electoral Commission (Inec) to review results from Ado-Ekiti, the capital of Ekiti state in south-west Nigeria.
A photo of the presidential election results from that ward should be shown with the signatures of party agents. But instead a photo of a woman is shown on the screen.
The BBC followed the same process - and the problem has yet to be fixed.
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It is unclear how widespread such errors are, but the revelation will pile even more pressure on Inec, which is being accused by opposition parties of bungling the election.
Inec has blamed technical issues for any hitches so far.
Joseph Jegede
BBC News, Abuja
A counter protest backing Nigeria's electoral body is full of voice outside the building in the capital, Abuja, where votes are being collated.
The tens of protesters are showing their support metres away from another group which is denouncing the Independent National Electoral Commission (Inec), accusing the body of running a non-transparent election.
The pro-Inec demonstrators are also carrying placards, one urges "Nigerians to stand up for democracy", another advises Inec to "complete your job" as tension rises over the results.
This morning three opposition parties called for the results to be scrapped, wanting fresh elections.
The announcement of official results is due to start here at the collation centre soon.
The PDP chairman at the recent press conference in the capital, Abuja, where his party along with two other opposition parties called for the cancellation of the election, called for calm.
“We don’t want Nigerians to erupt,” Iyorchia Ayu said.
Earlier, the police chief warned candidates and their parties against inciting violence.
The Independent National Electoral Commission (Inec) has confirmed there have been major technical hitches, which has made it difficult to upload results on to its server.
At the opposition press conference in Abuja, the PDP’s agent, Dino Melaye, said the problems with servers should have been corrected before any results were announced.
Joshua Ajayi
BBC News, Abuja
A group of angry protesters have gathered outside the national collation centre in Nigeria's capital, Abuja.
They are carrying placards denouncing the Independent National Electoral Commission (Inec), alleging votes have been stolen.
"Everything happening there is all lies, all lies, lies... they are cooking up results," one man told the BBC as he pointed to the Inec collation centre.
Tension is growing in the country, three days after Nigerians voted in an election marred in parts by violent disruptions and ballot box snatching.
Opposition parties have called for a fresh election, alleging that Inec has bungled the poll - an allegation the electoral body denies.
The announcement of official results is due to begin in the next half hour.
Image source, Getty ImagesA new electronic system was used to accredit voters for the first time
The main opposition party in Nigeria has expressed its concern over the conduct of Saturday's election, saying it was marred by "problems".
A statement by the Peoples Democratic Party (PDP) criticised the Independent National Electoral Commission (Inec)
"Let’s be clear, the election is inconclusive and the Inec chairman cannot proceed without the political parties being present to object or accept the results at the national collation exercise."
The opposition party urged poll officials to declare Saturday's election as "inconclusive" and to organise repeat polls in areas where the electronic voting machines were not used and where the exercise was disrupted by violence.
Both the PDP and the opposition Labour Party have alleged there was a lack of transparency with the new electronic system, which was being used to accredit voters for the first time.
Inec has denied the opposition parties' complaints.
Latest results show Mr Tinubu has garnered over 44% of the tallied votes. His main rival Atiku Abubakar has almost 33% of the vote.
Labour's Peter Obi, who is popular with younger voters in urban areas, has close to 18%, having caused an upset by defeating Mr Tinubu in the biggest city, Lagos.
Joshua Ajayi
BBC News, Abuja
Image source, Getty ImagesResults need to be certified and announced at the collation centre in Abuja before they become official
The national collation centre here in the capital, Abuja, has yet to start announcing results this morning.
Electoral officials says there are five states now ready to announce – but they will wait until 13:00 GMT (14:00 local time) to allow for more results to be ready.
On Monday, results were released from 14 of the country's 36 states.
Ruling APC party candidate Bola Tinubu is leading with just over 44% of the tallied votes. His main rival Atiku Abubakar from the PDP has almost 33% of the vote.
Labour Party's Peter Obi has close to 18%, having caused an upset by defeating Mr Tinubu in the biggest city, Lagos.
Nigerian presidential candidate Peter Obi, from the Labour Party, has won in the capital, Abuja - known as Federal Capital Territory (FCT), provisional results show.
Mr Obi got 281,717 votes followed by the ruling APC candidate Bola Tinubu, who polled 90,902 votes. Opposition politician Atiku Abubakar came in third with 74,199 votes.
This result needs to be certified and announced by the Independent National Electoral (Inec) Commission before it becomes official.
The Nigerian government has accused former President Olusegun Obasanjo of attempting "to undermine the electoral process" and "incite violence" after he cast doubt over the veracity of Saturday's election.
"Though masquerading as an unbiased and concerned elder statesman, former President Obasanjo is in reality a known partisan who is bent on thwarting, by subterfuge, the choice of millions of Nigerian voters,'' Information Minister Lai Mohammed said.
"What is expected from a self-respecting elder statesman are words and actions that douse tension and serve as a soothing balm."
In a statement released on Monday night, Mr Obasanjo said tension was building up in the country amid questions about whether the elections had been fair and transparent.
The 85-year-old asked President Muhammadu Buhari to “let all elections that do not pass the credibility and transparency test be cancelled”.
But Mr Mohammed countered, saying that Mr Obasanjo was not "qualified" to advise Mr Buhari. The information ministry tweeted the statement:
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"In his time, [he] organised perhaps the worst election since Nigeria's return to democratic rule in 1999," the information ministry statement quoted Mr Mohammed as saying.
Mr Obasanjo had warned that the country faced "looming danger" if allegations of voter fraud were not dealt with.
Mr Mohamed accused the former leader of promoting "unverified claims" and "wild allegations picked up from the street".
He went on to praise the electoral body, saying they had managed to act "creditably", and pointed to preliminary reports by the regional body Ecowas' Electoral Observation Mission and the Commonwealth Observer Group.
He added that anyone could contest the conduct of the election through the courts, but urged Nigerians to wait for the electoral commission to announce the official results.
More on Nigeria election results:
The announcement of results for the southern oil-rich state of Rivers have been suspended as the electoral official in charge has complained of death threats.
Charles Teddy Adias said he and his family had been threatened by those alleging he intended to rig the results - which he denies.
He says he will not collate any further results until this matter is addressed by the Independent National Electoral Commission (Inec).
The BBC's Nduka Orjinmo says Rivers state is a PDP stronghold but many of its young educated residents are supporters of Labour Party candidate Peter Obi.
There are also indications that its powerful governor Nyesom Wike, who is leading a rebellion within the PDP after losing at the primary last year to Atiku Abubakar, is backing the ruling APC party.
Our reporter says this will affect matters at the national collation centre in the capital, Abuja, as a winner cannot be announced until all the results are first collated at the state level.