A group of men set off a fire extinguisher on a train and another one on the platform, British Transport Police said.
Officers have released this CCTV image of the men they want to speak to following the drama on November 15 between 6.45pm and 7.15pm.
PC Gez Copper said: “A group of men who appeared to have been drinking, boarded the train at Preston, and generally made a nuisance of themselves to fellow passengers. During the journey, a fire extinguisher was set off, and a member of the public had to retrieve it from them.
“When the train arrived at Carnforth, another fire extinguisher was removed and let off on the platform.”
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