Stephen Kalonzo Musyoka as the President and the Deputy President of the Republic of Kenya.
Kenya's election commission confirmed there had been an attempt to hack into its system but said it had failed. Police fired on rioters in Kawangware, a poor area of the capital, said an Associated Press photographer.
The electoral commission said the poll was free and fair.
The observer missions included the Common Market for Eastern and Southern Africa (COMESA), the Commonwealth, East African Community (EAC), European Union (EU), International Conference of the Great Lakes Region (ICGLR), Intergovernmental Authority on Development (IGAD), National Democratic Institute (NDI) and the Carter Center (TCC).
The opposition candidate denounced this morning "a enormous fraud", committed by the Kenyatta party, who would have hacked the server of the Electoral Commission (CEK) and manipulated the voting results by using the identity of an official killed 10 days earlier in mysterious conditions.
But the opposition insisted it was in possession of alternative results, showing Odinga in the lead.
With 99 percent of the ballots counted Kenyatta is way ahead.
According to data provided by the Electoral Commission, the current incumbant leader of Kenya leads the initial results, holding 54.64 percent of the total votes.
According to Odinga, hackers had manipulated the IEBC servers to give President Kenyatta a constant 11 per cent lead over the opposition candidate.
Instead, the election board was displaying a running tally on its website that showed President Uhuru Kenyatta leading with 55 percent of the vote to Odinga's 44 percent after almost three-quarters of polling stations had reported results.
Mr Odinga had said hackers could have used the identity of a top election official, who was tortured and murdered days before the vote.
Mr Odinga said the results were the "work of a computer" and did not reflect the will of voters.
A senior police officer, who spoke on condition of anonymity, confirmed that two people had been killed in the slum of Mathare in Nairobi on Wednesday.
Kenyan police opened fire on people protesting election results earlier Wednesday in another opposition stronghold, killing one person.
The leading candidates have avoided using inflammatory rhetoric that could fuel tensions ahead of the vote, global election observers said.
Former president Mahama has been trying to calm choppy waters by urging the country's leaders to accept the results once it is officially declared by the country's electoral commission.