A Norwegian tourist who was assaulted and robbed by a large group in Melbourne last week has left Australia early.
Police say the group of young adults seem to have wrongly accused the tourist of taking photos of people.
The 34-year-old man was approached by up to eight people at St Kilda Pier about 1pm on Thursday in full view of bystanders.
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He was assaulted and his phone was stolen and thrown into the water.
Detective Senior Constable Jesse Coppel said the group accused the victim of taking photos of people at the pier.
"During the course of the confrontation he's shown his phone to the offenders, proven that he's not done it and they've proceeded to assault him anyway," Coppel said.
"The information we have indicates that people have seen the contents of his phone prior to it being destroyed and there was nothing of that material or that nature on the phone.
"It seems to me as if they have used this as an excuse to confront this man and when it's not followed through they've assaulted him anyway regardless."
Coppel described the behaviour was "disgusting" and people deserved to be able to enjoy the beach peacefully.
"People behaving in this way is deplorable, it doesn't belong here," he said.
The man was taken to hospital with a broken arm and has since returned home despite previously intending to spend Christmas in Australia.
Coppel said police had not been able to speak with him at length.
The offenders fled the scene but police have released images of four people they wish to speak with.
All four people are believed to be aged in their early 20s.
The first man is described as being of Mediterranean/Middle Eastern appearance, approximately 165cm tall with a thin build, short goatee beard and black curly hair.
He was wearing black shorts and sunglasses.
The second man is described as being of Caucasian appearance, approximately 175cm tall with a medium build, short goatee beard and short brown hair.
He was wearing an open grey short sleeve shirt, blue camouflage shorts, a black New York Yankees beanie, black Nike runners and carrying a sports bag.
The third man is described as being of Caucasian appearance, approximately 170cm tall with a thin build and curly hair with shaved sides. He may be in his late teens.
He was wearing a Chicago Bulls #13 jersey, black Nike shorts, black Nike slides and carrying a black satchel bag.
The woman is described as being of Caucasian appearance, approximately 160cm tall with a slim build and dark hair.
She has a number of distinctive tattoos on her chest, leg and arm and was wearing a red bikini.
Anyone who witnessed the incident or recognises one of those described is urged to contact police.
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