Kenya's electoral body has limited access to the national tallying centre in order to speed up the process of verifying presidential results.
Anyone who is not a party agent, election observer or part of the media should leave the centre.
The verification of results has been stopped several times after complaints by supporters of the main candidates.
Confirmed results show former Prime Minister Raila Odinga has a slight edge over Deputy President William Ruto.
With 93 of the 292 constituencies declared, he has 52% of the vote against 47% for Mr Ruto.
However, provisional results tallied by media organisations using official data from the 46,000 polling stations show a tight race between the two candidates. About 14 million votes were cast - a turnout of 65%.
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The electoral commission has up to Tuesday next week to declare the winner.
"We have to make adjustments" to quicken the process of verifying results, the head of the electoral body Wafula Chebukati said in his latest briefing on Saturday.
"It's taking three to four hours" to process one each results from a single constituency, he said. "Some of our returning officers have stayed here for three days sitting on chairs which is totally unacceptable."
He announced that additional staff would help clear the remaining 124 poll officials, as well as give party agents copies of the remaining results forms which they can compare with those sent electronically.
Extra police officers have also been drafted in.
"We believe that this will fasten the process and we should be able to dispose of the returning officers in the course of today," Mr Chebubati said.
Media tallies of results from more than 46,000 polling stations - posted on the electoral commission's website - have caused some confusion in the country because the counts didn't match.
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Officials denied claims on social media that fake results had been posted after the system hosting the results was hacked.
"Nothing like that has happened. It is misinformation," said the electoral commission's CEO Marjan Hussein Marjan.
What is happening at the main tallying centre?
Based at a cultural centre called Bomas in the capital, Nairobi, officials from the Independent Electoral and Boundaries Commission (IEBC) are busy verifying results.
Security has been enhanced at the venue and access to the compound limited.
Electoral officials are comparing photographs of result forms from more than 46,000 polling stations nationwide to physical forms being brought to centre by officials from each of the 290 constituencies.
This is to ensure that the results match.
Mr Chebukati had accused agents from the main parties, who are witnessing the process, of turning a straightforward exercise into a "forensic" one.
How are Kenyans feeling?
There is a sense of anxiety in the country as disputed elections in the past have led to violence or the whole process being cancelled.
Following the 2007 vote, at least 1,200 people were killed and 600,000 fled their homes following claims of a stolen election.
In 2017, huge logistical errors led the Supreme Court to annul the result and order the presidential poll to be re-run.
Officials are under pressure to get things right this time.
The country often grinds to a halt during elections, activities across the country have slowed and schools remain closed at least until next week on Monday. In Nairobi's central business district, the usually busy streets are mostly deserted.
Allegations of election rigging are as old as the country. It was part of politics even before multiparty elections were re-introduced in the 1990s, but the push for free and fair elections has never faltered.
After the violence that followed the 2007 election, political parties and activists argued for the use of technology instead of physical registers, which could be easily manipulated, to verify voters.
This year's election is the third time technology has been used but it has yet to deliver an election that has not been challenged in the courts.
When will we know the result?
It's unclear when the final results will be known, but the electoral commission has ramped up the verification of the results.
If there is a clear leader of the race, celebrations are likely to break out - but only the IEBC can make it official.
To win the presidential race in the first round, a candidate needs:
more than half of all the votes cast across the country
at least 25% of the votes cast in a minimum of 24 counties.
Otherwise voting goes to a second round which by law has to happen by 8 September.
Click here to see the BBC interactive
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