When the driver lost control of the truck on Kursela bridge, it broke the railings and fell on the train before skidding off on the track.
The accident occurred between Kursela and Kataria stations under the East Central Railway (ECR) in the wee hours, the sources said.
Though no casualty of injury was reported from among the passengers, the cleaner of the truck was injured and was admitted to hospital.
The train service on Katihar-Barauni section remained disrupted for about four hours before the the truck was removed from the track, the sources added.