Violence in Nigeria's northeast has gained in intensity since April, when more than 200 schoolgirls were snatched by Boko Haram rebels from Chibok. Efforts to free them have so far not succeeded.
The attackers yesterday made simultaneous strikes on two villages in the Chibok community, in Borno state.
Samuel Chibok, a survivor of the attack on Kautikiri village, said that around 20 men in a pick-up truck and motorcycles rolled into town. They sprayed it with bullets, focusing much of their fire power on a local church.
"Initially I thought they were military but when I came out, they were firing at people. I saw people fleeing and they burned our houses," he said.
A pro-government vigilante said residents had recovered 15 bodies.
Another attack on Kwada, five miles (8km) from Chibok village, left some people dead, a security source said.