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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The plaque at number 16 Cowley Street in Westminster marks the brown brick Georgian townhouse where Sir John lived for 31 years.
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Metropolitan Police officer, Tom Harrison, has been crawling the course since the race began on Sunday morning.