Kenya's Supreme Court has annulled the result of last month's presidential election, citing irregularities, and ordered a new one within 60 days.
The ruling makes Kenya the first African country to have a presidential poll invalidated by a court.
The election commission had declared incumbent Uhuru Kenyatta the winner by a margin of 1.4 million votes.
But the opposition argued that the commission's IT system had been hacked to manipulate the results.
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Chief Justice David Maraga said the 8 August election had not been "conducted in accordance with the constitution" and declared it "invalid, null and void".
He said the verdict was backed by four of the six Supreme Court judges.
The announcement drew cheers from opposition supporters both inside and outside the courtroom.
