Armed men carried out the bloodshed on Friday in the village of Ntumbo in the Northwest region, James Nunan, a local official of humanitarian coordination agency OCHA said.
A massacre in an anglophone region of Cameroon left up to 22 villagers dead including 14 children, the UN said on Sunday, with an opposition party blaming the killings on the army.
Armed men carried out the bloodshed on Friday in the village of Ntumbo in the Northwest region, James Nunan, a local official of humanitarian coordination agency OCHA, told AFP.
"Up to 22 civilians were killed, including a pregnant woman and several children," Nunan said, adding that 14 children under age 18 – including nine under age five – were among the dead.
Eleven of the children were girls, said Nunan, head of OCHA's office for the Northwest and Southwest regions, which are home to the West African country's large English-speaking minority.
Separatists in the regions have been fighting the central government for three years.
The Movement for the Rebirth of Cameroon, one of the country's two main opposition parties, issued a statement saying: "The dictatorial regime (and) the supreme head of the security and defence forces are chiefly responsible for these crimes."
A key figure in the separatist movement, lawyer Agbor Mballa, in a Facebook post also accused "state defence forces" of carrying out the killings.
The three-year conflict between anglophone forces seeking to break away from French-speaking Cameroon has claimed more than 3,000 lives and forced more than 700,000 people to flee their homes.
Friday's killings followed elections on February 9 that were marred by violence in the regions blamed both on separatists and security forces.