Four villages in north-eastern Nigeria have been attacked by suspected Boko Haram militants who targeted at least one church.
The bodies of at least 40 civilians and six militants have been recovered, a local vigilante has told the BBC.
It is the latest assault on villages near Chibok, the town where more than 200 schoolgirls were abducted in April.
Hundreds of villagers have been killed in similar attacks in the region by Boko Haram in recent months.
A state of emergency is in force in northern Nigeria because of the group's increasingly violent campaign to overthrow the government and create an Islamic state.
Attacks in the Chibok area eight days earlier were feared to have left dozens of villagers dead.
The BBC's Will Ross: "We are hearing reports of totally deserted villages"
Bows and arrows
An eyewitness said Kautikari village, a short distance from Chibok, was almost deserted, with bodies of civilians and Boko Haram fighters on the streets.
The insurgents were there for at least four hours, setting fire to homes and shooting sporadically.
Vigilantes armed with bows and arrows and hunting rifles have been trying to defend the village from such attacks.
One of the survivors said some 20 men arrived in a pick-up truck and on motorbikes, Reuters reported.
"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," Samuel Chibok was quoted as saying.
"Smoke was billowing from our town as I left."
The BBC's Will Ross, in the commercial capital Lagos, says a Nigerian air force plane has been seen flying over the area.
However, residents of these extremely vulnerable villages often complain that there are not nearly enough soldiers deployed in the area and they have been calling on the government to arm the vigilante force, our correspondent adds.
AFP news agency named the other villages targeted as Kwada, Ngurojina and Karagau.
According to one account from Kwada, a number of churches there were attacked during Sunday services and worshippers killed before the militants went on to Kautikari.
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