Nairobi - Kenya's main opposition coalition demanded on Thursday that its candidate Raila Odinga be declared president, claiming it had evidence he had won an election that has already led to angry protests over fraud claims.
The latest allegations by the National Super Alliance (NASA) are likely to further ratchet up tensions a day before official results are expected from Tuesday's vote.
President Uhuru Kenyatta has an unassailable lead in provisional results, but Odinga claims these are a "sham" result of a massive hacking attack on the electronic vote tallying system.
Heads of foreign observer missions from the European Union, African Union, Commonwealth and Carter Center urged party leaders to be patient and refrain from inflaming tensions, expressing confidence in the election commission (IEBC).
However shortly after they spoke, one of NASA's leaders Musalia Mudavadi gave a televised press conference unveiling new claims from "confidential sources" within the IEBC that their servers showed Odinga was the true winner.
Mudavadi said he would provide data and screenshots showing that on the IEBC servers, Odinga was shown to have 8.04 million votes against Kenyatta with 7.75 million.
The IEBC public website, which is publishing results as they stream in electronically from polling stations, shows Kenyatta with 8.1 million votes ahead of Odinga with 6.7 million.
According to the website, results are in from 98% of polling stations, however the IEBC has urged patience as it cross-checks results with scanned forms.
"Evidently, the accurate and lawful results in the presidential election is the transmission received from the polling stations and contained in the IEBC servers and not the unverified displays," said Mudavadi.
"We demand that the IEBC chairperson announce the presidential election results forthwith and declare Raila Amolo Odinga... as the duly elected president."
Mudavadi however urged Kenyans to "remain calm at this point in time."
IEBC chief Wafula Chebukati had earlier urged parties to "exercise restraint" as results were being finalised.
"We are working hard to ensure that we get the final results within the shortest time possible. We expect that all the presidential results... will reach the national tallying centre by 12:00 tomorrow (Friday)."
He said the results would be validated and that a final decision would be announced "soon thereafter."
Odinga, 72, who claims elections in 2007 and 2013 were stolen from him, on Wednesday charged that hackers broke into the IEBC's systems and rigged the count using the log-in details of top IT official Chris Msando, found murdered and tortured last month.
"You can only cheat a people for so long," Odinga said.
His allegations sparked isolated protests in his strongholds in several Nairobi slums and the western city of Kisumu on Wednesday, where protesters engaged in running battles with riot police.
The capital's police chief said officers shot dead two men who had allegedly attacked them with machetes.
In the southeastern Tana River region, police killed two alleged knife attackers who stormed a vote-tallying centre and stabbed one person.
On Thursday many businesses remained closed and the streets were very quiet in the capital and elsewhere as the country held its breath, with memories still fresh of post-election violence in 2007 that left 1 100 people dead.
"We find ourselves at a crossroads once again," the Daily Nation newspaper warned grimly.
"The nation is sitting precariously on the precipice. The dispute over poll results is creating needless anxiety."
The IEBC insists its electronic voting system - seen as key to avoiding fraud - had not been compromised, despite apparent attempts to do so.
"Hacking was attempted but did not succeed, that is our position," said Chebukati.
Former US Secretary of State John Kerry, leading an observer team from the Carter Centre, expressed confidence in the integrity of the electronic system.
"We believe the IEBC put in place a detailed, transparent process of voting, counting, reporting and securing the vote, all of which lends significant credibility and accountability," Kerry told a press conference.
Polling officers have been sending results electronically to Nairobi, which are showing up in real time on a public website, but these need to be backed up with forms signed by them and party agents in each of the 40 883 polling stations.
Kerry said his observer team had witnessed party agents counting ballots and deciding together which were valid or not before signing off on final tallies.
"All of this provides an extensive traceable trail of agreement by many parties on the paper balloting process and therefore on the outcome," he said.
Some 400 international observers were present for Tuesday's vote.
Marietje Schaake, head of the EU mission said elections commission (IEBC) officials were "working around the clock. It's important they have the time to do these procedures well."
"We continue to urge everyone to be calm, to be resilient and to be peaceful," she said.
Ghanaian former president John Mahama, who is leading the Commonwealth delegation, also urged Kenyans to give the IEBC "proper time and space to complete the results process with necessary due diligence.
"It is vital that all political leaders maintain peace and calm, exercise patience and not stampede the process," he added.