Posted by Cops have released CCTV of a man they would like to speak to
A man, travelling on the bus with a group of four or five other men, is said to have sexually assaulted the woman.
Officers launched an investigation into the horror incident and are now appealing for witnesses.
Anyone who was travelling from York races to York train station at around 7pm who may have witnessed the incident is asked to contact the police.
North Yorkshire Police is keen to hear from anyone who recognises the man pictured.
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