An eight-year-old girl and her mother who were travelling to Assam were among the four passengers who died in the train derailment near Buxar in Bihar, a railway official said.
The eight-year-old girl has been identified as Akriti Bhandari and her mother Usha Bhandari (37). The girl's father, who was also travelling with them, survived the accident.
Narendra Kumar from Rajasthan and Abu Zayed (27) from Purnia were the other two who lost their lives when the 12506 North East Express derailed near Raghunathpur in Buxar district on Wednesday night.
Zayed's friend, who was travelling with him, survived the accident.
Apart from the four dead, several people were injured when 23 coaches of the train, on the way to Assam from Delhi, derailed near the Raghunathpur station.