The incident took place yesterday. The train was bound for Bangladesh's capital Dhaka.
The husband of the woman had complained to the station manager at Kolkata about the incident after which the Border Security Force (BSF) was informed.
"Constable V Bhavi of the 99th battalion of the force has been found involved in the incident and he has been suspended," a senior BSF officer said.
He said the jawan was part of the contingent that is tasked to provide security to the cross-border train till it enters Bangladesh from Gede in West Bengal.
The Maitree Express, launched in 2008, runs between Kolkata and Dhaka on four days a week.
Disclaimer: No Business Standard Journalist was involved in creation of this content