Millions of voters will cast their ballots across Guinea Sunday to choose a new president in the country's second democratic presidential election. Polling will close at 18:00 GMT Sunday.

Incumbent President Alpha Conde is facing tough fight from seven other candidates, including former prime minister and main challenger Cellou Dalein Diallo, according to BBC News.

Cellou Dalein Diallo said Saturday that he would participate in the election. President Alpha Conde had earlier rejected Diallo's demand to postpone the election.

"We will vote, defend our suffrage, defend our victory because there is no way we will let our victory be stolen," said Diallo, DW reported.

Conde's seven rivals, however, said that they would not recognize the results. "The seven candidates will not recognize the results which will be made following an election with anomalies and irregularities," they said in a joint statement, according to AFP.

The vote comes after days of pre-election violence in the impoverished West African nation. At least three people have been killed in election-related violence since Thursday, the Associated Press reported.

The United Nations chief Ban Ki-moon deplored the recent violence and called on all parties to uphold their commitments.

"I have received worrying reports of violent unrest and looting in Conakry, Guinea. These new incidents come after a series of violent clashes between supporters of Guinea's ruling party and members of the opposition last week in the southwestern city of N'Zerekore, which left more than 45 people injured," UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein said in a statement.