The Supreme Court has nullified the re-election of President Uhuru Kenyatta.
A six-judge bench, by majority decision, on Friday found that the electoral commission failed to conduct the polls according to the Constitution and Elections Act.
"Elections is not an event but an process. After considering the totality of the entire evidence, we are satisfied that the elections were not conducted in accordance to the dictates of the Constitution and the applicable principles," Chief justice David Maraga said.
"That President Uhuru Kenyatta was not validly elected on August 8.".
Judges Ojwang and Njoki Ndung'u dissented while judge Mohammed Ibrahim, who fell ill on the second day of the case hearing, did not take part in the decision because he is still in hospital.
The top court in Kenya, in a bold move, ordered the IEBC to conduct a fresh presidential election within strict confines of the law within 60 days.
Lawyers who represented President Kenyatta and the IEBC protested the judgment and sought explanations and clarifications from the judges.
Lawyer Ahmednasir Abdullahi, for Mr Kenyatta, faulted the court, saying it had made a political decision because no one is disputing that the voter made his decision.
According to him, Lady Justice Ndung'u upheld the wishes of Kenyans.
But Justice Maraga said, in due time, they would be able to demonstrate why they reached their decision.
The decision was greeted with celebrations in regions perceived to strongholds of National Super Alliance (Nasa) leader Raila Odinga and his running mate Kalonzo Musyoka.