Villagers say suspected Islamist extremists have attacked several farming settlements in Nigeria's northeast Borno state this week, killing 18 people and razing homes.

Wadai Mutah said Friday 10 people were killed and several injured on Tuesday before attackers set the whole village on fire near the state capital, Maiduguri. Maiduguri is the birth place of Boko Haram, the terrorist network whose name means "Western education is forbidden."

Mutah said eight people were killed in a neighboring village on Wednesday. He said Mude and Kwaljiri villages were destroyed, but residents escaped unharmed.

Boko Haram has killed thousands of people in its four-year mission to impose Shariah law and attacks continue despite an 8-month-old state of emergency.

Locals have formed vigilante groups to fight back but attacks have increased, likely in retaliation.