Debasish Das, son of Trinamool Congress MLA Kasturi Das and brother-in-law of the Kolkata Mayor, was on Sunday found dead under mysterious circumstances at Barsoi railway station in Katihar, Bihar, an official said.
The GRP men found his body lying on the railway track near the outer signal of platform number two of Barsoi railway station, superintendent of police, Railway, Jitendra Mishra said.
It was not immediately clear whether the 45 year-old's death was an accident or a murder, he said.
Das could have fallen down from a Kolkata-bound train late on Saturday night and injury marks were found on his head, he said.
The victim's mother Kasturi Das is an MLA from Maheshtala assembly constituency in West Bengal.
The body has been sent for post-mortem to ascertain the cause of his death, Mishra said.
Debasish's father Dulalchand Das and brother-in-law Shobhan Dev Chattopadhyaya, who is the Kolkata Mayor, were on their way to Barsoi to take possession of the body, the SPR said.