Cameroon's President Paul Biya says he is confident his ruling party will preserve its overwhelming majority in parliament after Sunday's elections.
President Paul Biya is rumoured to want another term in office
He said a victory for the Democratic Rally of the Cameroonian People would help him to "modernise the country".
No results have yet been released. But the leader of the opposition SDF party, John Fru Ndi, called the polls "a sham" and alleged widespread fraud.
Critics say President Biya, in power for 25 years, runs a repressive regime.
His party holds 149 of the 180 seats in parliament.
Opposition to Mr Biya is limited, and only 5.5m of the 18m population signed up to vote.
"What I expect right now is a comfortable majority, which will enable me to build and modernise the country," President Biya said after casting his ballot in Yaounde.
He said that the campaign took place in a "peaceful atmosphere", and he hoped that the country would "accept the verdict of the polls".
President Biya's term in office is due to come to an end in 2011.
BBC correspondents say there are reports he wants to maintain his big majority to enact legislation allowing an extension of his rule.
No ballot papers
The opposition, meanwhile, said there was widespread fraud during the voting.
It said indelible ink used to mark those who had already voted easily washed off and that some people had been refused ballot papers.
"The elections are a sham," Mr Ndi said.
He also alleged that ballot papers had not even been delivered to one town in northern Cameroon.
"We have learnt that Biya wants to modify the constitution to run for a third term. This we cannot allow to happen." Mr Ndi told Reuters news agency.
Mr Biya's critics say he has presided over a repressive system. They say there was also widespread fraud in earlier ballots.
But his supporters say he has held Cameroon together and in peace.