"The accurate and lawful results in the presidential election is the transmission received from the polling stations and contained in the IEBC servers", he said.
Supporters of opposition leader Raila Odinga on Thursday said an unofficial tally shows that he won.
North Eastern Regional coordinator Mohamud Saleh says police are trying to restore calm after part of the town's market was burnt by arsonists.
Meanwhile, International election observers Thursday called for restraint as Kenyans await the announcement of the official results from the nationwide polls.
Election officials have disputed Odinga's claims that hackers infiltrated the election commission's database and manipulated results against him.
Former US Secretary of State John Kerry, an observer for the Atlanta-based Carter Centre, said Kenyans could rely on the vote tally forms, which were signed by party agents at more than 40,800 polling stations and posted online by the commission, to ensure that the final result was fair.
In an unexpected turn of events, the National Super Alliance presidential candidate, Raila Odinga, showed up at the Bomas of Kenya national tallying center on Friday, August 11.
All eyes will now turn to Odinga, and his reaction to the loss which he claimed was a result of massive rigging of Tuesday's election, which his party denounced as a "charade" and a "disaster".
While veteran opposition leader Odinga, 72, claimed 2013 polls were stolen from him, he took his grievances to the courts and ended up accepting his loss.
But confrontations emerged a day later between police and protesters in opposition strongholds in the capital and the western city of Kisumu, leaving at least two people dead.
In Mathare slum in Nairobi, where the capital's police chief said officers shot dead two men who had allegedly attacked them with machetes on Wednesday, scores of people streamed through the street shouting "Uhuru must go".
The provisional results from Tuesday's vote gave Kenyatta a substantial lead over Odinga.
On Wednesday, he said that the IT system of the Independent Electoral and Boundaries Commission (IEBC) had been hacked, and Kenya was witnessing the worst "voter theft" in its history.
As Kenya faces the prospect of another disputed election, there were fears of a reprise of the ethnic violence that killed an estimated 1,500 people after a similar dispute in 2007.
"Hacking was attempted but did not succeed, that is our position", said Chebukati.
Kenyatta is already on track for a win (97 percent of stations reporting, Kenyatta: 54.32 percent; Odinga's 44.8 percent).
Head of the EU's election mission Marietje Schaake confirmed Kerry's assessment of the voting, and said she had seen "no signs of centralized or localized manipulation".
Over 400 worldwide election observers - including officials from the United States and the European Union - were deployed across the country to monitor voting, the tallying process and part of the post-election period. He claimed the hackers used the identity of Christopher Msando, an election official in charge of managing information technology systems.
"We affirm the conviction that the judicial process, the judicial system of Kenya, and the election laws themselves make full and adequate provision for accountability in this election".
The IEBC insists its electronic voting system - seen as key to avoiding fraud - had not been compromised, despite apparent attempts to do so.
"Even if I am celebrating, let me celebrate in a way that will not provoke the other person because if I celebrate in a way that provokes another person, that escalates that feeling of people fighting of which we don't want", said Otieno.
As the final results deadline approaches, we shall see what transpires with this election!
"We also appeal to Kenyans to await the final outcome as determined by the IEBC, which must be given the time and space to complete its important work, including investigating any evidence of fraud", he said.