A portion of the Bardhaman Railway Station building collapsed on Saturday evening, an Eastern Railway official said.
Work is on to remove the debris and look for people who might be trapped under it, he said.
"The portion of the station building at Bardhaman collapsed at 8.10 pm," the ER spokesman said.
Construction activity was underway at the site where the collapse took place, another official said.
Bardhaman Railway Station, located about 95 km from Kolkata, is on the busy Howrah-New Delhi line.
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