Police are investigating an assault in Melbourne earlier this month.
Investigators have been told the victim and his wife were walking across Flinders Street near the intersection of Market Street about 12pm on 2 November.
It is believed the couple were approached by a male offender who asked them what they were looking at before punching the victim in the back in an unprovoked attack.
The victim received serious injuries and required medical treatment.
Police have released images of a man they believe may be able to assist with their enquiries.
The man is described as Caucasian in appearance, aged in his mid-30s with short fair coloured hair and was wearing a long black skirt, dark coloured jacket and brown sandals.
Anyone who witnessed the incident or anyone who knows the identity of this man is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential crime report at www.crimestoppersvic.com.au
Sergeant Megan Stefanec