Police are searching for a man who spat on a Metro Trains worker in an unprovoked attack earlier this month.
Police said the man spat on the staffer on platform one at Clifton Hill Station about 7.55pm on Friday April 21.
The man then fled by jumping on a Flinders Street Station-bound train.
Police have released images of a man they believe may be able to assist with their inquiries.
The man was described as Caucasian, aged in his late 20s to early 30s and between 172 to 177 centimetres tall.
He had a small to medium build and black, messy collar-length hair, dark bushy eyebrows and dark stubble.
On the night of the incident the man was wearing a green and white trucker cap with unknown black writing on the front. He was also wearing a black jacket, maroon pants and white and red runners with a red Nike tick.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000.