The explosions took place at T Minou village area, about 130 kms south-east here, at around 9 PM last night, they said.
No individual or group has claimed responsibility for the blast.
Official reports from the spot said some militant outfits were active in the area.
Unidentified militants had attacked a post of 39th Assam Rifles near Indo-Myanmar border some days ago, but no casualty was reported, reports said.