Three women were attacked by two couples on a Waterloo-bound train following Ascot races.
The women used foul and abusive language towards the two couples- two men and two women.
The abuse continued on Richmond train station where the three women tried to attack the group of four before running away.
British Transport Police are continuing their investigation after receiving CCTV footage of the three women they want to speak to about the incident on Friday, June 21.
PC Neil Allison said: "This is a particularly violent and aggressive attack on two couples who had not done anything to provoke it.
"This is believed to be a very busy train service, with many of the passengers returning from a day at Ascot races. I am sure that other passengers on the train and at Richmond station may have information key to our investigation."
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