British Transport Police officers investigating several incidents of indecent exposure are appealing for any witnesses to make contact.
On Sunday 3 September, at around 11.30 am, a man was seen exposing himself on five occasions on various platforms at Derby railway station and onboard a train.
The station manager alerted police and a 26-year-old man was arrested at the station. He has since been bailed pending further investigation.
The suspect is described as black, medium build, short dark hair and he was wearing grey casual clothing.
Officers are asking any witnesses to make contact by calling 0800 40 50 40, or by texting 61016 with the reference 2300103501.
Information can also be given anonymously to the independent charity Crimestoppers on 0800 555 111.
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