Fifteen-year-old Himel left his home on his bike on Thursday and never returned
The accident took place around 6am on Saturday on the south end of Laksam Railway Junction, on duty Traffic Inspector Masud Sarwar told bdnews24.com.
He said the Noakhali-bound Samatat Express was sent to the wrong track because of a point man's error. Four wheels of the last bogey went off the tracks when the driver tried to stop the train, he added.
The train was not removed from the spot and the tracks were not repaired until 8:30pm. Officials said repair works would take at least an hour.