Kenya’s supreme court has declared the results of last month’s presidential election invalid and ordered a new vote. Incumbent Uhuru Kenyatta won 54% of the now-nullified vote, defeating opposition leader Raila Odinga.

“The presidential election was not conducted in accordance with the constitution, rendering the declared results invalid, null and void,” Kenya’s chief justice David Maraga said in its Sept 1 ruling. According to Maraga, the court found “irregularities and illegalities” in the transmission of results. He ordered the electoral commission to hold a fresh presidential election within 60 days.

Cheers outside the courtroom and across Nairobi could be heard, with crowds chanting, “Uhuru must go!” and cars beeping their horns. Residents in Kisumu, an Odinga stronghold, also flocked to the streets to celebrate.

Reuters/Thomas Mukoya Time to celebrate.

Odinga, claiming Kenya’s electronic electoral system was hacked to rig the results in favor of Kenyatta, had petitioned the court to examine the election. The Independent Electoral and Boundaries Commission (IEBC) denied the results were hacked and international observers said they witnessed no signs of manipulation. The court invalidated the election with a majority of five of seven judges. The dissenters, Jackton Ojwang’ and Njoki Ndung’u, said none of the irregularities “occurred deliberately and in bad faith.”

The court, which said it would deliver its full judgment within the next 21 days, said a total of 5 million votes had not been verified. An IT expert for the court found irregularities such as blank ballots and votes from non-existent polling stations. The court also said unauthorized users had accessed the electronic electoral system before and after election day.

The decision throws Kenya into a state of uncertainty. It’s not clear whether the current members of the electoral commission will need to be replaced. The Nairobi Securities Exchange halted trading for half an hour after an index of its 20 largest companies fell by more than 5%.

President Kenyatta on Friday called for calm and peace, and said that he was ready to go back to the campaign trail and face voters again. “I personally disagree with the ruling that has been made today,” Kenyatta said. “But I respect it as much as I disagree with it.”

Odinga for his part said the court’s decision was “a first in the history of African democratization.” Surrounded by supporters in front of the supreme court offices in Nairobi, Odinga called the ruling “a triumph for the people of Kenya.”

Wafula Chebukati, chairperson of the electoral commission, said he would not resign but that the IEBC would make changes to its personnel and processes. He called for the office of the director of public prosecution to probe and prosecute officers who may have broken the law.

AP Photo/Sayyid Azim Kenya’s supreme court decides.

The court’s move is unprecedented in Kenya and the continent more broadly. Globally there are few examples of a high court nullifying a presidential election—Ukraine in 2004, the Maldives in 2014, and Austria in 2016.

Kenya’s sixth election since introducing multi-party democracy in the 1990s, has been marred by widespread public mistrust, fake news, and in some cases violence. A week before the election, a senior election official was found dead, apparently tortured, outside of Nairobi. After election results were released, police cracked down on protesters in parts of Nairobi, killing at least 24 Kenyans, including a 10-year old girl and a six-month old baby.

Locals and foreign observers have worried about a repeat of Kenya’s 2007 election, when disputed results ended in post-election violence that claimed the lives of at least 1,200 people and displaced more than half a million.

Holding another presidential poll within the next two months is likely to tax a country that has already spent at least $1 billion on the election. Matt Carotenuto, associate professor of history of African Studies at St. Lawrence University in New York said, “What comes next? Endless campaigns, protest, voter apathy and further legal challenges? Certainly all of the above, as Kenya’s economy will also suffer as citizens await the next tense presidential election in 60 days.”