At least four persons have been killed in Cameroon?s largest city, Douala, as police and opposition protesters clashed ahead of the announcement of presidential election results, according to the regional governor.

The clashes on Sunday came after hundreds of supporters of opposition candidate Issa Tchiroma ? who claims to have defeated President Paul Biya in recent elections ? defied a protest ban and gathered in the streets of Douala.

The protesters barricaded roads, burned tyres and threw rocks and other projectiles at police, according to the Reuters news agency.

The police responded with tear gas and water cannon.

Samuel Dieudonne Ivaha Diboua, the governor of the region that includes Douala, told the AFP news agency that the protesters went on to attack police stations in the second and sixth districts of the city.

Several members of the security forces were wounded, and ?four people unfortunately lost their lives?, he said.

Tchiroma?s campaign also confirmed the deaths.

The protests came after partial results from the October 12 election, reported by local media, showed that Biya, who is 92 years old, was on course to win an eighth term in office.

But Tchiroma claimed he won 54.8 percent of the votes against Biya?s 31.3 percent, and called on Cameroonians on Wednesday to protest if the Constitutional Council announces ?falsified and distorted results?.

Cameroon?s government has rejected the opposition?s accusations of irregularities and urged people to wait for the official election results to be announced by the Constitutional Council on Monday.

Protests have since flared in several cities, including the capital, Yaounde, Tchiroma?s hometown, Garoua, as well as Maroua, Meiganga, Bafang, Bertoua, Kousseri, Yagoua, Kaele and Bafoussam.

Speaking from Douala, journalist Blaise Eyong told Al Jazeera that the country?s youth, who make up the majority of the population, were particularly ?furious? at the alleged vote rigging by Biya?s camp.

?You can really see the frustration and anger when you talk to young people,? added Eyong, who noted that there are high rates of youth unemployment in Cameroon.

Amid reports of government blackouts, Eyong confirmed that the internet had been disrupted across the country in recent days. ?But that has not stopped young people from coming together,? he said.

Earlier on Sunday, Tchiroma?s campaign manager said that authorities had detained about 30 politicians and activists who had supported his candidacy, heightening tensions.

Among those he said were detained were Anicet Ekane, the leader of the MANIDEM party, and Djeukam Tchameni, a prominent figure in the Union for Change movement.

Cameroonian Minister of Territorial Administration Paul Atanga Nji said on Saturday that arrests had been made in connection with what he described as an ?insurrectional movement?, though he did not say who ? or how many ? had been detained.

Biya is the world?s oldest serving ruler, and has been in power in Cameroon since 1982. Another seven-year term could keep him in power until he is nearly 100.

Tchiroma, a former minister and one-time Biya ally, has said that he won and that he will not accept any other result. (Al Jazeera)

Update news