A man threw a bottle at a teenage boy before assaulting him at the bottom of a Tube escalator.
British Transport Police have said that the incident took place at West Ham underground station at around 2.45pm on September 20.
The attack at the bottom of the Jubilee line escalator resulted in the 15-year-old boy losing consciousness and bleeding from his mouth.
Detectives have now released images of a man they believe may have information that could help their investigation.
Anyone who recognises him is asked to contact British Transport Police by texting 61016 or by calling 0800 40 50 40 quoting reference number 2300111116 of 20 September.
Alternatively, you can call Crimestoppers anonymously on 0800 555 111.
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