Nigeria's most prominent opposition party, the Peoples Democratic Party (PDP), won the governorship election in Osun state, one of 8 of Nigeria's 36 states where the governorship elections weren't being held at the same time as the rest of the country. The results were a blow to President Muhammadu Buhari's ruling party, the All Progressives Congress. 

The Independent National Electoral Commission (INEC) said Senator Ademola Adeleke of the Peoples Democratic Party (PDP) got 403,371 votes, which essentially unseated the APC governor, Gboyega Oyetola, who gathered 375,027 in the election on Saturday. 

Adeleke won 17 out of 30 local governmental areas, whereas Oyetola won in 13, sparking celebrations in the streets of Osogbo. 

On Sunday, Buhari congratulated Adeleke, who has been crowned the 10th governor since Nigeria became a state in 1991. 

"With the election over, the president expresses conviction that the people of Osun have expressed their will through the ballot, and the will of the people must always matter and be respected in a democracy," Buhari's office said in a statement.

"The president reassures the nation that the commitment of this administration towards having credible elections remains unshaken," it added.