BTP officers are today releasing CCTV images after a report of robbery at Maghull North station in Merseyside.
The incident happened at 1.25pm on Sunday 3 March.
A man is reported to have approached the victim in the waiting room on platform 2, threatened him with a knife and demanded his bicycle.
After a struggle, the suspect left with the bike. The victim chased the man and the two continued to fight in another area of the station.
The fight ended when the suspect was disturbed by a witness.
The victim suffered a bite on the shoulder, bruising on his cheek, and scratches on his finger.
Officers believe the man in the images may have information that can help their investigation.
Anyone who knows the identity of the man, or who witnessed the incident, is asked to contact BTP by texting 61016 or by calling 0800 40 50 40 and quoting reference 249 of 03/03/19.
Alternatively, call Crimestoppers anonymously on 0800 555 111.
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