Jewish communities are on edge after separate alleged anti-Semitic attacks on a synagogue and two other locations in one night, as police step up patrols and counter-terrorism officers stand ready.
Twenty congregants were forced to flee a synagogue in East Melbourne on Friday night after a bearded man in his 30s allegedly doused the building's front door with flammable liquid before setting it alight.
Police said they were lucky no one was injured in the targeted act of anti-Semitism on the same night when protesters allegedly smashed a window, flipped tables and threw chairs outside Israeli restaurant Miznon in the CBD.
The group of protesters had splintered from a larger demonstration in the city before making their way to the establishment in Hardware Lane, where they allegedly chanted "death to the IDF", referring to the Israel Defence Force.
A 28-year-old protester was arrested for hindering police, as detectives sift through CCTV as part of investigations.
Hours later, offenders allegedly spray-painted three cars and a wall outside a Greensborough business in Melbourne's northeast before setting fire to the vehicles, destroying one and damaging two.
Police said there were "inferences of anti-Semitism" and that the business had been "subjected to pro-Palestinian activity" in the past 12 months.
Detectives have issued a photo of a man they wish to speak to over the synagogue attack.
They say they are not aware of any links between the three incidents as they continue their probes and have flagged a review of their response to a pro-Palestine demonstration in Melbourne on Sunday.
"Our investigators across all three incidents are liaising with our counter-terrorism command," Commander Zorka Dunstan said.
None of the incidents have been declared terrorism-related but the force is increasing patrols around the synagogue and in the city's southeast.
"We understand incidents of anti-Semitism can leave communities feeling targeted, threatened and vulnerable," Cmdr Dunstan said.
The attack on the 150-year-old temple was the 10th firebombing the Australian Jewish community has experienced in the past 12 months, Executive Council of Australian Jewry president Daniel Aghion said.
"If you think about terrorism as creating terror or fear, then yes, it is a form of terrorism," he said.
"This is a pattern of behaviour designed to create fear amongst the Jewish community, which it will not do."
Anti-Defamation Commission's Dvir Abramovich said diners were terrorised and Melbourne "stopped being a safe place for Jews" for one night.
Prime Minister Anthony Albanese condemned the alleged synagogue arson as a "cowardly" act of violence and anti-Semitism and slammed the attacks on the restaurant and business as unacceptable.
The federal government has offered federal police and security and intelligence agency support to investigators.
"Those responsible for these shocking acts must face the full force of the law," he said.
The attacks come seven months after a blaze destroyed two buildings at the Adass Israel Synagogue in the city's south and forced worshippers inside to flee.
No charges have been laid, although counterterrorism police have raided multiple properties as part of that investigation.
Israel's foreign minister condemned Friday's attacks and demanded Australian do more to combat anti-Semitism.
"Israel stands firmly with the Jewish community in Australia," Gideon Sa'ar posted on social platform X.
"There have been too many anti-Semitic attacks in Australia.
"The Australian government must do more to fight this poisonous disease."