After the assault, the suspect got off the bus and headed towards Lambeth Walk. The victim, who has not been named, was taken to St Thomas' Hospital with a head injury and released later that day.
The suspect is described as a light-skinned black man of slim build. He is approximately 20-years-old and wearing a black T-shirt with a patterned pocket on the chest, dark trousers and a baseball cap worn back to front.
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