The minors, belonging to the adivasi community, were on their way by bus to Rupa in neighbouring Arunachal Pradesh when they were intercepted by the police and taken into custody.
The arrested person has been identified as Chandra Kumar Rai and the children have been handed over to parents, sources added.
Children were taken from their home in a tea estate in Dhekiajuli in Assam's Sonitpur district, police said.