flee their homes, residents said Saturday.
"The terrorists stormed Maikadiri around 9:00 am (0800 GMT Friday) and opened fire on hapless citizens," resident Simon Templer said."They laid siege in daylight because there are no soldiers or police nearby," said another survivor, Markus Ali, adding: "We counted 21 corpses."
The attackers "killed, destroyed and then fled," Ali said.
Two other villages close to Maikadiri in southern Borno state were also attacked, said Maina Ularamu, chief of the Madagali district.
"The gunmen arrived on 10 motorbikes, two or three on each bike and attacked Kopa, Maikadiri and Yaffa" villages, he told AFP.
He said four people were killed in Yaffa.
He claimed that the extremists used to live in the villages before joining Boko Haram.
"Now they have no limits and they are preying on their own community because of the pressure the army offensive has put on them," Ularamu said.The villages hit are on the fringes of the vast Sambisa forest, a longstanding hideout of the Islamist insurgents.
The Nigerian army has led a series of raids against them in recent months, succeeding in freeing several dozen women and children from the hands of the jihadists.
Ularamu said the extremists may have been taking their revenge on their former neighbours.
"The attacked their community because they would not let them back when the army attacked their camps. Those who tried to come back were denounced and arrested by the authorities," he said.
Fatima Saleh, who lives in the neighbouring village of Maigana, told AFP she saw the attackers pass and recognized many of them as locals.
Several state officials in the region have said this week that Boko Haram is still active in the forest despite the military offensive against them.
A police officer in the Borno state capital Maiduguri confirmed the attacks while requesting anonymity.
Templer said many homes were also destroyed in the attacks.
"My aged mother is currently in the bush. Most of our people have fled and many houses and shops have been burnt," he said.
The Boko Haram insurgency and efforts to quell it have claimed more than 15,000 lives and displaced 1.5 million people since 2009.
A new wave of violence has already killed more than 800 since Nigeria's new President Muhammadu Buhari took office in May pledging to stamp out the Islamists.