Police have released CCTV stills of a man they would like to speak with in relation to an incident on train between Waterfall and Mortdale railway station.
About 10.15pm on Friday, September 21, 2018, a 49-year-old woman boarded a train at Albion Park Railway Station heading north.
A man boarded the same train at Helensburgh Railway Station.
Between Waterfall and Mortdale Railway Stations the man has allegedly indecently assaulted the woman in the toilet area of the train before they were involved in an altercation.
About 11.47pm, the man got off the train at Mortdale railway station.
The incident was reported to police from the Police Transport and Public Safety Command and an investigation commenced.
Officers have now released CCTV of a man who may be able to assist with their inquiries.
The male depicted in the photographs is described as being of Caucasian appearance, aged in his 30s, about 170cm - 175cm tall, of a medium build, and with brown hair.
He is shown wearing jeans, a dark shirt, black shoes, and has tattoos on his arms
Police are urging anyone with information, or anyone who knows the identity of the man to come forward.
Police are urging anyone with information in relation to this incident to call Crime Stoppers on 1800 333 000.