Voters in Cameroon head to the to the polls Sunday to elect a president for a new seven-year term.

Incumbent Paul Biya is widely expected to extend his 29-year rule over the central African state because the opposition has again failed to solidify behind one strong candidate.

In the last election in 2004, Mr. Biya won a landslide victory with 70 percent of the ballots

The 78-year old leader is facing 22 candidates in Sunday's election. His main opponent again is Fru Ndi who had a strong showing in the 1992 election, but won only 17 percent of the vote in 2004.

The opposition has accused Cameroon's electoral commission of being biased in favor of the ruling party and there have been complaints about irregularities on voter lists.

A top member of the election board, Elecam, was fired days before the poll on allegations of violating the oath of office by campaigning for President Biya.

Mr. Biya has ruled Cameroon since 1982. In 2008 he eliminated term limits mandated by the constitution so he can run for re-election this year. The move sparked street protests in which at least 40 people were killed.

This year's campaign has been marked with tensions and analysts are warning of possible post-election violence in the nation frustrated over high unemployment and the rising cost of living.