A 42-year-old man was set upon after he accidentally bumped into one of the men as he walked through the Mulgrave car park to a hotel just after midnight on Saturday.

Police said they understood around 100 people were present during the attack and “no-one rendered immediate assistance, even after the offenders fled”.

Eventually someone driving by found the injured man and called an ambulance.

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The victim was treated at the Alfred Hospital for a head wound that required 13 stitches, as well as arm and upper body injuries.

Police said the offenders were described “as being of Middle Eastern appearance”.

Detective Senior Constable Chris Duke from the Monash Crime Investigation Unit said it was “a sad state of affairs” to think that a large group stood back and watched the assault without trying to intervene.

“I’m appealing to the people who witnessed this assault on Saturday morning to come forward and tell us what happened,” he said.