The man then calmly walked away from the woman towards platform four and onto a train.
Luckily the victim was not left with any visible injuries, but this was a shocking and unprovoked assault.
We do not tolerate violence like this anywhere on the rail network and I'd urge anyone who recognises the man pictured, or who may have witnessed what took place, to come forward and assist officers in this investigation.
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A 24-year-old man has been arrested on suspicion of murder after the body washed up on the Thames shoreline.
Seven people have now been arrested after a man died from serious head injuries
The 38-year-old officer was on his way home from a night shift when he collapsed. His death is not being treated as suspicious.