The Dehradun-bound Muzaffarpur-Rapti-Ganga Express hit the overcrowded tempo at Samera railway crossing in East Champaran district.
East Champaran superintendent of police Sudhir Kumar Singh told IANS over telephone: "Bodies of all the victims have been sent for post-mortem."
Divisional railway manager (Samastipur) Arun Malik told reporters at the site that the accident was the result of a negligence on the part of the gateman at the railway crossing.
Malik said the railway safety commissioner will inquire into the accident.
According to reports reaching here, all the victims are from one family.
The Bihar government announced a compensation of Rs.1.5 lakh to the kin of the victims and the railway has announced a compensation of Rs.50,000 to the kin of victims.