Yaounde, Cameroon (CNN) -- The head of Cameroon's election commission denied opposition candidates' allegations of fraud in Sunday's ballot, saying the process was "more transparent" than in the past.
"Throughout the entire process, no major incident was reported," Fonkam Azu'u, election commission chairman, said Monday. "Nevertheless Elections Cameroon will draw the necessary lessons in order to better organize future polls."
Opposition candidate Jean de Dieu Momo told reporters he had received reports of improperly sealed ballot boxes. Ballot boxes were missing from some polling stations as well, he said, echoing a sentiment shared by Edith Kah Walla, an opposition leader.
International observers have yet to weigh in on charges of fraud and voting irregularities.
Cameroonians went to the polls Sunday amid relative peace and calm nationwide. There were threats of violence ahead of the vote.
Biya, 78, who has been in power for nearly 30 years, cast his ballot under heavy security. He is seeking another seven years in office.
Election officials have up to 15 days to announce election results, but cabinet minister Laurent Esso predicted a landslide victory for Biya shortly after he cast his ballot Sunday.
In 2007, Biya won 70% of the vote in a race against main opposition leader John Fru Ndi.