The bomb was detected by a patrol party of 9th Assam Rifles battalion from a place at the international line in Moreh on Thursday and later defused, the police said.
It is being suspected that the bomb was planted by militants to attack security personnel posted in the border town where Assam Rifles, Border Security Force and other forces were posted, the police said.
Moreh, about 120 Kms south-east of here, is an important border town since international trade between India and Myanmar is conducted daily there.