Hundreds of protesters have clashed with security forces in several cities across Cameroon, a day before the results in a highly-contested presidential election are due to be announced.

Police fired tear gas and water cannons at the supporters of opposition candidate Issa Tchiroma Bakary in his stronghold of Garoua, a city in the north of the country.

The protesters were denouncing what they said was a plan by the ruling party, the Cameroon People's Democratic Movement (CPDM), to steal the victory from the opposition leader.

Tchiroma Bakary has insisted that he won the presidential election held on 12 October, challenging incumbent President Paul Biya's 43-year hold on power. The CPDM has dismissed the claims.

The demonstrations come after Tchiroma Bakary called on his supporters in the country and the diaspora to march peacefully to liberate Cameroon. Authorities have banned gatherings until Monday, when Cameroon's constitutional council is set to announce the results.

In Garoua, the demonstrations began peacefully but quickly turned rowdy when security forces threw teargas on the streets to disperse the hundreds of people that had gathered in support of Tchiroma Bakary.

Protesters carried placards demanding justice and called for transparency in the election results. Supporters also rallied in the south-western city of Douala, chanting, We want Tchiroma!.

Tchiroma Bakary claims to have won 55% of the vote based on results from individual polling stations but faces a reality where the constitutional council, appointed by Paul Biya’s administration, has dismissed allegations of electoral irregularities.

Born in Garoua, Tchiroma previously served as Biya's communications minister before breaking away to run for presidency, further complicating an already tense political landscape in Cameroon.