Twelve bikes with a combined value of nearly £5,000 have been stolen from a number of train stations.
Bicycles have been taken from stations across Hertfordshire including Watford Junction, Kings Langley, St Albans City, Hemel Hempstead, and Apsley.
The thefts happened during the day between July 2 and September 3 of this year.
Investigating police officers are linking the thefts and they would like to speak to the man pictured in all four CCTV images.
The British Transport Police believe the man pictured may have information which could help them with their investigation.
Anyone who recognises the man are has any information that may help with the investigation is asked to call 0800405040 or text 61016 quoting 343 of September 19 or you can call Crimestoppers anonymously on 0800555111.
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