Police have since confirmed the man was detained but not arrested, and acting assistant commissioner Rhys Wildman said alleged “breach of the peace” was behind the decision.
“That male was removed from the vicinity of South Bank Parklands and taken to another location and released without charge,” he told reporters.
“There was conflict between the protest group and this male who we had to detain and remove, largely for his own safety.”
Attempts by this masthead to identify the man and speak to him were not immediately successful.
A Hamas flag was also allegedly flown at the rally, attracting condemnation from police and politicians after photos emerged on Sunday evening.
Wildman confirmed officers were investigating the matter, but had not yet tracked down the person responsible.

A photograph of the Brisbane rally shows what appears to be the Hamas flag in green and white.Credit: William Davis
“That’s a Commonwealth offence. It is being investigated and we are taking that matter very, very seriously,” he said.
“We are keen to speak to that particular male and the investigation is very much alive this afternoon.
“It’s disappointing that in among a protest group where the majority of people are trying to get a particular message across, there are still individuals that will do their own actions and behave in a way that is not in keeping with the rest of the group or the broader community sentiment.”
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Hamas is a designated terrorist group in Australia and was behind the October 7 attacks in Israel that killed about 1200 people. About 250 people were taken hostage.
The incursion sparked a ferocious military response from Israel that has extended for almost two years and killed more than 60,000 Palestinians.
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