Updated

Suspected Boko Haram militants have killed dozens of people in northeast Nigeria after opening fire at crowds who were urged to gather inside a church, a local politician says.

The attack has been one of several the past few days in the Mandara Mountains, a Boko Haram stronghold that borders Cameroon, according to the BBC.

Residents from the village of Attagara said their church was first targeted by militants on Sunday, when 20 people reportedly were killed. A few militants were allegedly killed by villagers in retaliation.

On Tuesday, the militants returned but were dressed as soldiers and claimed they had arrived to protect the village, parliament member Peter Biye told the BBC.

"They came in mass in military uniform with about 200 motorcycles… they said they came to rescue them [and] they should not run away," Biye said.

Biye said villagers were then urged into the church before the militants opened fire and burned buildings.

Those who fled the scene reported seeing many bodies.

Boko Haram, which has kidnapped hundreds of Nigerian schoolgirls, has been waging and insurgency in Nigeria in a bid to create an Islamic state.

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