“Such conduct is designed to ostracise Jewish businesses and intimidate the Jewish communities. These actions are designed to inflict fear and instil division. This matter should be referred to police and investigated as a priority.”

Allegra Spender,a federal independent MP who was concerned last weekend to see the symbol on display in her Sydney electorate at a kite flying event on Bondi Beach,said its appropriation needed examination.

“I went and looked at the history of the symbol and my concern is about what it is trying to do,” she said. “It really has no place on a family day which should be about bringing people together and celebrating.”

The symbol is known as the Abu Obeida triangle,named after the spokesman for the Hamas military wing,and was first used by the terrorist group’s Al-Qassam brigades to identify targets such as Israeli tanks and soldiers for lethal strikes. Since October 7,the symbol has morphed into an online meme and emoji shared by Hamas sympathisers and more recently,pro-Palestinian activists,including some unaware of its origins.

The symbol is outlawed in Germany because of its direct association with Hamas,a proscribed terrorist organisation that has controlled Gaza since 2007 and planned and ledthe October 7 attack on Israel,when 1200 people were murdered and more than 200 kidnapped. The attack provoked Israel’s ongoing,deadly reprisals in Gaza.

Josh Roose,a Deakin University political sociologist and expert in political and religious violent extremism,said Hamas had carefully chosen the red triangle or red arrow – a symbol that features in the Palestinian flag – to maximise its appeal.

“It is actually a very sophisticated tactic,” Roose said. “It has clearly been used by Hamas in their military videos. It has been picked up by their activists and now used by the anti-Israeli,global protest movement.

“If you call that out,you are accused of trying to outlaw the Palestinian flag,which then creates more outrage and victimisation.”

Executive Council of Australian Jewry co-chief executive Alex Ryvchin said the symbol had become a de facto Hamas flag.

“Just as neo-Nazi groups have long evaded scrutiny and accountability by shifting from the swastika to various derivative symbols or code words,the pro-Hamas movement has done likewise,” he said.

“But the aim is clear. It is to show support for Palestinian violence and revel in the killing of more Israelis.”

Greens MP Tim Read,the Brunswick parliamentarian contacted by Cohen after his Lygon Street business was first marked with the symbol in July,said he was very concerned by the episode and had raised it with Merri-bek Council and police.

“Vandalising Jewish-owned businesses is unacceptable and antisemitic behaviour,which I completely condemn,” he said. “I encourage people to be critical of Israel’s continued bombing of civilians without attacking Jewish people,many of whom are protesting Israel’s actions.”

Palestinian community leader Nasser Mashni deplored the targeting of a Jewish-owned business but declined to comment on the use of the symbol more broadly. “The Australia Palestine Advocacy Network opposes all violence against civilians,in Australia or anywhere else,” he said.

The war in Gaza,which is approaching its first anniversary,is estimated by Palestinian authorities to have killed nearly 43,000 people.

In December,the federal parliament bolstered Australia’s counter-terrorism laws by inserting a new provision into the criminal code prohibiting the public display of hate symbols. Although the law change explicitlyoutlaws Nazi and Islamic State symbols,it also created a new offence,punishable by up to a year’s jail,for anyone who knowingly displays a symbol used to identify a terrorist organisation.

A memorandum circulated by Attorney-General Mark Dreyfus to explain the purpose of the law change said violent extremists used symbols to spread their ideology to a wider audience and recruit followers. “Ideologically and religiously motivated violent extremists within the community are seeking to publicly display and trade symbols of hate with the intent of promoting hatred,instilling fear and harassing others,” the memorandum noted.

Dreyfus last weekintroduced legislation to criminalise the practice of doxxing – the publishing of private,identifying information with malicious intent – after the details of 600 members of a Jewish chat group were distributed online by pro-Palestinian activists.

Dutton said the targeting of a Jewish-owned business with a Hamas symbol was “precisely the type of conduct” that should be captured by change to the criminal code. “We have the laws to deal with these acts of intimidation and hate. The government and our law enforcement agencies need to swiftly use them,” he said.

Cohen contacted the Brunswick police station about the threatening symbol,but police did not respond. Merri-bek Council promised to conduct an investigation but closed the case a week later without taking action.

“The police were horrified,the council were horrified,and they did nothing about it,” Cohen said. “Jewish hatred has become a weed.”

Brunswick East and other suburbs in Melbourne’s inner north,which are currently subject to a fierce political contest between Labor and the Greens ahead of next year’s federal election,are at the epicentre of the pro-Palestine protest movement in Australia.

Cohen,a self-described cultural Jew who has lived in the area for 20 years and has run the Brunswick East Wine Store for a decade,said he was disturbed by the parallels between the marking of his business by anti-Israel activists and the way Jewish businesses were identified and targeted during the rise of the Nazis nearly 100 years ago.

He is now reconsidering the future of his business.

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