A bike storage facility at Preston Railway Station has seen two bikes taken in recent weeks.
British Transport Police have released a picture of a man they wish to speak to in connection with the incident.
Both bikes were taken from the Bike Hub in Butler Street by the side of the station.
Police say the first bike was taken at 2.50pm on 27 October and a second at 3.41pm on 1 November.
The first bike taken was unlocked while a second bike was taken using cutters to break through the lock.
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Anyone with information is asked to call British Transport Police on 0800405040 quoting reference 516 19/11/18.
Alternatively you can call Crimestoppers anonymously on 0800555111.
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