Myanmar police will begin arming and training non-Muslim residents in the troubled north of Rakhine State, where officials say militants from the Rohingya Muslim group pose a growing security threat, police and civilian officials said.

Human rights monitors and a leader of the mostly stateless Rohingya said the move risked sharpening intercommunal tensions in a region that has just seen its bloodiest month since 2012, when hundreds of people were killed in clashes between Muslims and ethnic Rakhine Buddhists.

Soldiers have poured into the Maungdaw area along Myanmar's frontier with Bangladesh, responding to coordinated attacks on three border posts on Oct. 9 in which nine police officers were killed.