President Uhuru Kenyatta has won re-election in Kenya, defeating veteran opposition leader and longtime rival Raila Odinga in a tense contest.

Kenya’s election commission declared Friday, August 11, 2017 that the 55-year-old businessman and son of the country’s founding president had received enough votes to secure a second five-year term.

Kenyatta garnered 54.27% of the final vote, similar to what he had in a preliminary count. Odinga received 44.74%.

The nation’s top elections official, Wafula Chebukati, said the vote was carried out in a “free, fair and credible manner.”

Odinga, a 72-year-old former political prisoner who has campaigned for the presidency four times, is refusing to accept the results, claiming the vote was hacked.

Speaking before the declaration, Musalia Mudavadi, co-principal of the opposition’s National Super Alliance (NASA), said they would not be party to the announcement of Kenyatta as president, citing unresolved concerns about the veracity of the electoral process.

“The issues we raised have not been adequately addressed,” he said. “One can conclude that they (Kenya’s Independent Electoral and Boundaries Commission) were not keen on taking our concerns seriously.”

James Orengo, NASA party chief agent, described the process as a “disaster.” “This has been an entire charade. The judgment is now out there in the court of public opinion.”

Odinga, running as the NASA candidate, told CNN Thursday that he doesn’t “trust” the paper forms from polling stations around the country that officials used to authenticate votes.

Odinga said the forms could have been “manipulated” before being returned to the capital. At a news conference Thursday, members of Odinga’s party gave no evidence to support any claims of election tampering, citing only unnamed sources at the election commission.

In a letter released Friday morning, Chebukati, the chairman of the election commission, rejected the opposition coalition’s evidence of election fraud, calling it “obviously and plainly falsified.”

On Thursday, Chebukati said tampering with the election system “was attempted but did not succeed,” without elaborating further.