An altercation broke out between two strangers at Preston railway station, British Transport Police tweeted on Wednesday (February 2).
Spotting the incident unfold, a member of staff attempted to intervene to calm the situation.
As he led one of the parties away he was punched in the side of the face by a 15-year-old boy.
"The youth was detained at the scene and he'll be interviewed in due course," a spokesman for BTP added.
If you have witnessed or been the victim of a crime while travelling on a train or at a station, British Transport Police are here for you.
Call BTP on 0800 40 50 40 or text 61016 to report any crime that has already happened, to seek crime prevention advice or to make them aware of issues in your neighbourhood.
Using the Freefone number above keeps 999 available for emergencies, and helps BTP reach the people who need them the most as quickly as possible.
Click HERE to find out more.
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