Deputy President William Ruto was declared on Monday the winner of Kenya's hard-fought presidential poll, but the announcement was mired in controversy after several members of the election commission rejected the results.

Independent Electoral and Boundaries Commission (IEBC) chairman Wafula Chebukati said Ruto had won almost 7.18 million votes (50.49%) in the August 9 vote, against 6.94 million (48.85%) for his rival Raila Odinga.

"I stand before you despite intimidation and harassment. I have done my duty according to the laws of the land," Chebukati said. 

"In accordance with the law, I... hereby declare that Ruto William Samoei has been duly elected as the president."

Shortly before his announcement, four out of seven IEBC commissioners said they could not recognize the results, raising rigging fears in the closely-watched poll in the East African political and economic powerhouse.

Ruto is a 55-year-old rags-to-riches businessman who had characterized the vote as a battle between ordinary "hustlers" and "dynasties" who had ruled Kenya since independence from Britain in 1963.

After the results were announced, he vowed to work with "all leaders" in Kenya.

"There is no room for vengeance," Ruto said, adding, "I am acutely aware that our country is at a stage where we need all hands on deck."

The outcome was a bitter blow for Odinga, the 77-year-old veteran opposition leader who had the weight of the ruling party behind him after forging a 2018 pact with outgoing President Uhuru Kenyatta in a stunning shift of allegiances.

The days-long wait for the outcome of the race had already set the East African nation on edge.

But in a shock announcement, IEBC Vice Chair Juliana Cherera told reporters that she and three of her colleagues could not "take ownership of the result that will be announced," calling the process "opaque".

"However we have an open door that people can go to court and because of the same we urge Kenyans to be peaceful because the rule of the law is going to prevail," she added.

Although last Tuesday's poll passed off largely peacefully in the regional political and economic powerhouse, memories of vote-rigging and deadly violence in 2007-08 and 2017 still loom large.

The IEBC had been under intense pressure to deliver a clean election after it faced stinging criticism for its handling of the 2017 election. 

Read more: Kenya: Ruto-Odinga elections spark flashbacks of violence

Since 1991, when the one-party state ended, Kenya has had six multiparty elections following pressure from civil society and donors. All elections since then have been high-stakes ethnic contests.

In the 2017 elections, Kenyans witnessed violence at extreme levels. About 100 were killed in post-poll protests, and in 2007 polls more than 1,200 people were killed in riots. 

Facebook's failure in detecting hate speech in Kenya ahead of elections has also sparked fears of reigniting chaos among tribes. Commissioners from Foxglove and Global Witness have criticized the social media company for blocking ads that are "dehumanizing, comparing specific tribal groups to animals and calling for rape, slaughter, and beheading."

It is not impossible that Kenya could break up along ethnic lines. Already the violence in the past has caused the flight of several hundred thousand Kenyans who belonged to ethnic minorities in their places of residence.

Although Kenya has for some time been referred to as a "model" by the imperialist West, the speed with which the entire social and political structure of what appeared to be one of the most stable countries in Africa shows the underlying fragility of bourgeois democracy everywhere.