Whitehorse Crime Investigation Unit detectives are appealing for public assistance after a man was seriously assaulted at a Box Hill hospital last night, Victoria Police say.
It is believed a man was walking into the Arnold Street premises about 7.20pm when he became involved in a verbal dispute with a male standing in the foyer.
The second man then hit the man to the head causing him to fall to the ground and fled the scene.
The victim, who is aged in his 40s, was transported to another hospital with life-threatening injuries.
Detectives are hoping to identify the man and have released CCTV images of the man in the hope someone may recognise him.
The offender is described as Caucasian in appearance, aged 20 to 30-years-old with a medium build.
He was wearing all black clothing and a black cap at the time of the incident.
Anyone who can identify the man or with any other information is urged to contact Crime Stoppers.