The Thai Army said three Thai soldiers were injured in a landmine explosion on Saturday morning during a patrol operation along the border.

Three Thai soldiers on patrol were wounded Saturday when one stepped on a land mine in territory along the border with Cambodia, Thailand’s army announced. The incident came just two days after the two countries reaffirmed their adherence to a ceasefire to end a brief armed conflict.

Thailand says the blast happened in its territory recently cleared of landmines, and will complain to Cambodia for violating a landmine ban treaty; phnom penh denied the allegation.