At least two police officers have died in fresh violence in western Cameroon where English-speaking separatists have declared an independent state, the military said on Sunday.
The men were killed by armed pro-independence fighters near the town of Wum in Northwest Region, an army spokesperson said.
The separatist camp spoke of nine police dead.
Army spokesperson Colonel Didier Badjeck said, on Facebook, that 21 of the attackers had been "neutralised", without saying how many had been involved in the assault.
Separatist unrest in Cameroon's two minority English-speaking regions - northwest and southwest - has left scores dead and displaced around 200 000 people since late 2016.
About 30 000 of those displaced have crossed the border into neighbouring Nigeria.
Years of resentment at perceived discrimination at the hands of the Cameroon's francophone majority have led to almost daily acts of violence and retribution.
Security in the two regions has deteriorated significantly since late last year and now clashes with separatist fighters are almost daily occurrences. A total of 109 members of the police and security forces have been killed, according to government figures.
The conflict poses problems for the organisation of the presidential election, scheduled for October 7, in which the 85-year-old incumbent, Paul Biya, is bidding for a seventh consecutive term.
Anglophones today account for about a fifth of the West African country's population of 22 million.
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