Police have released CCTV images after an alleged unprovoked attack in Sydney’s inner west left a man with a fractured skull.

On the morning of September 18, emergency services were called to the intersection of Bay Street and Grose Street, Glebe, following reports a man had been assaulted.

The 60-year-old man had been walking north along Bay Street, when he was hit in the stomach by another man walking past him.

The younger man, believed to be aged in his 20s, then allegedly turned and struck the older man in the back of the head before fleeing.

The 60-year-old was taken to Royal Prince Alfred Hospital with serious head injuries, including a fractured skull.

NSW Police have released CCTV images of a man they believe may be able to assist them with their inquiries.

Detective Acting Inspector Michael Egan-Hirst told Jim Wilson said it was an “innocuous” bump that apparently lead to the attack.

“It’s a sickening attack, a definition of a coward punch if I’ve ever seen one,” he said.

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“It’s a miracle that the victim is alive but he says he doesn’t feel the same,” Ben Fordham said.

“He was left with a 25cm laceration on his skull, he’s had to have surgery, he may have permanent brain damage.

“The victim is terrified, he can’t remember what happened.”

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