Kenya's electoral commission chairman has admitted its database was a target of an unsuccessful hacking attempt, but it has failed to convince the opposition, which on Thursday said results showed their leader Raila Odinga had won.
Wafula Chebukati's remarks came on Thursday following allegations by opposition leader Odinga that hackers infiltrated the database and manipulated results in favour of President Uhuru Kenyatta after Tuesday's vote.
Chebukati said "hacking was attempted but did not succeed" and tallying of final results was continuing.
With results from 97.6 percent of polling stations counted, Kenyatta held a strong lead.
On Thursday, opposition coalition leader Musalia Mudavadi told journalists that "confidential sources" within the IEBC had revealed the "actual results", showing Odinga had won the presidential poll with 8.04 million votes against incumbent Kenyatta with 7.75 million.
The electoral commission received endorsement from the European Union observers on Thursday. EU said they saw no signs of manipulation in the voting process, calling on whoever wins the election to try to heal political divisions in the country.
"After such competetive elections, it is now time for Kenyan politicians to bring the people together and work towards an inclusive and socially cohesive society for all Kenyans," David McAlister, an EU observer, said at a news conference in Nairobi.
A team headed by former US Secretary of State John Kerry also called for calm and restraint on Thursday, as protests called by the opposition turned violent on Wednesday claiming the lives of at least five people.
Kerry also told Al Jazeera that the allegations need to be examined but "not a reason to stop the process or question the entire election".
"The [counting] process is still ongoing, the counting is happening now. And as long as it's done appropriately, you have an ability to have full integrity of this election. The integrity is still intact."
Thabo Mbeki, the former South African president in charge of the African Union observer mission, has praised the poll so far.
"It would be very regrettable if anything emerges afterwards that sought to corrupt the outcome, to spoil that outcome," he said.
Al Jazeera's Catherine Soi, reporting from the opposition stronghold Kisumu, said she spoke with Odinga's campaign team members and close advisers who still insist that the voting system was hacked.
"Raila Odinga says he needs an independent investigation into the poll and people here are saying that they have every confidence in him. They will believe everything he is going to say," she said.
Odinga's claims were enough to spark isolated protests in his strongholds in several Nairobi slums and the western city of Kisumu on Wednesday.
A relative peace returned to the streets on Thursday. There was violent protests in just one Nairobi neighbourhood, Kawangware slum, where police fired live rounds and tear gas as they clashed with opposition supporters
However, at least five people have been killed in post-election violence in Kenya after opposition leader Raila Odinga claimed "massive" fraud in Tuesday's vote.
Two people were shot dead in the capital Nairobi on Wednesday, said the city's police Chief Japheth Koome, claiming they took advantage of the protests to steal.
At least one more person was shot dead earlier in the day in South Mugirango constituency in Kisii County, around 300km west of Nairobi, during a clash with the security forces, according to Leonard Katana, a regional police commander, the AP news agency reported.
In the southeastern Tana River region, police said five men armed with knives had attacked a vote tallying station and stabbed one person to death.
"Our officers killed two of them and we are looking for others who escaped," said regional police chief Larry Kieng.
"We have not established the motive yet, we don't know if it is political or if it's a criminal incident but we are investigating and action will be taken."
In the port city of Kisumu, the hometown of Odinga, police used tear gas and shot at supporters of the opposition leader, said demonstrator Sebastian Omolo.
"He is not accepting the results and that is why we are on the streets, but police have started shooting," Omolo said.
Al Jazeera's Hamza Mohamed:
Most shops and businesses centres remained shut for the second day in Nairobi as people waited for the presidential results.
On the streets of Kibera, the country's biggest slum, young men stood on street corners glued to their mobile phones looking for updates.
Everyone is keeping an eye on what the opposition leaders will do if Kenyatta is declared the winner.
Odinga lost to Kenyatta in 2013 and went to court. He lost the legal challenge and Kenyatta was confirmed as the president.
It is not clear if Odinga is willing to go court again.
Kisumu shopkeeper Festus Odhiambo said he was praying for peace even as protesters blocked roads into city slums with bonfires and boulders.
The contest between President Uhuru Kenyatta, a wealthy 55-year-old businessman, and Odinga, 72, a former political prisoner and son of Kenya's first vice president, has been a hard-fought election that stoked fears of possible violence.
Odinga rejected the partial results of the presidential polls, saying hackers infiltrated the database of Kenya's election body to manipulate the "democratic process".
The opposition leader said that he could not reveal his sources on how he got the information on the alleged hacking.
In a press briefing that took place in the capital Nairobi, the presidential candidate said his party's results are "completely different" from those published on the election commission website.
Al Jazeera's Fahmida Miller, reporting from Mombasa, said that Odinga was alleging that important forms have not materialised from the tallying stations.
"Once the votes are tallied and transmitted electronically, these forms are meant to back up exactly how many votes were given to each particular candidate to validate what exactly has gone on," she said.
Wafula Chebukati, the head of Kenya's electoral and boundaries commission, said at a news conference: "As a commission we shall have our own investigative system to kick in. We shall come up with a methodology to find out whether or not those claims are correct."
On Wednesday morning, the election commission website showed Kenyatta leading with 54.4 percent of the votes against 44.8 percent for Odinga, a margin of nearly 1.4 million votes, after 94 percent of the votes were counted.