A ticket inspector had a brick thrown at him by a man who refused to cooperate when asked to show his train ticket.
After becoming verbally abusive towards the inspector, the man was removed from the train at Maryland station.
As he was leaving, he picked up a house brick and threw it, hitting the inspector on the torso.
Police are appealing for any witnesses to the incident, which happened at around 2.20pm on Tuesday, July 24, to come forward.
They have described the man as being Asian, of slim build and approximately 25 to 30 years old, with short black hair and a short beard. He was wearing a black hoodie, dark trousers and white trainers.
Anyone with information should text British Transport Police on 61016 or call 0800 40 50 40 quoting reference 353 of 24/07/2018.
You can also ring Crimestoppers anonymously on 0800 555 111.
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