At least 140 people were killed by gunmen who attacked remote villages over two days in north-central Nigeria’s Plateau state, survivors and officials said Tuesday in the latest of such mass killings this year blamed on the West African nation’s farmer-herder crisis.

The assailants targeted 17 communities during the “senseless and unprovoked” attacks on Saturday and Sunday, during which most houses in the areas were burned down, Plateau Gov. Caleb Mutfwang said Tuesday in a broadcast on the local Channels Television.

“As I am talking to you, in Mangu local government alone, we buried 15 people. As of this morning, in Bokkos, we are counting not less than 100 corpses. I am yet to take stock of (the deaths in) Barkin Ladi,” Gov. Mutfwan said. “It has been a very terrifying Christmas for us here in Plateau.”