The incident took place at Boisar station at 10:10 am when commuters with monthly season tickets (MST) entered the 22956 Bhuj-Bandra express train and began occupying berths alloted to passengers with reserved tickets, he explained.
He added that as the argument between the two groups intensified, some passengers pulled the train's alarm chain, leading to the train halting out of schedule at the station.
The cascading effect left another suburban train from Dahanu delayed by over 40 minutes, the official said.
He added that a case had been filed with the railway police and investigations were underway.