Paul Biya retains his title as the world's oldest head of state, in an election marred with violence and allegations of fraud.

DOUALA (Reuters) -Cameroonian authorities have detained about 30 politicians and activists linked to opposition presidential candidate Issa Tchiroma, his campaign said Sunday, heightening tensions ahead of Monday's announcement of results of an October 12 election.

Cameroon's President Paul Biya has won re-election at the age of 92. Opposition supporters who say the election was rigged have been protesting against him.

Cameroon's opposition leader Issa Tchiroma Bakary, who has declared himself the winner of the 12 October elections, has told the BBC that he will not accept a stolen vote, with the results due to be announced on Monday. He says his team has compiled the overall picture based on results from individual polling stations, so there is no doubt.

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