In the dark of early Tuesday morning, "Glory to Hamas" was painted on a large billboard above a Fitzroy shop on the corner of Alexandra Parade and Brunswick St in Melbourne's inner north.
The words "Free Palestine" and "Oct 7, do it again" also appeared on the side of a building further along Alexandra Parade on the corner of Smith St.
A bike and skate shop in Northcote was also spray-painted, with the damage reported to police when staff arrived the next day.
The same group of three are believed to be responsible for the graffiti attacks, police confirmed on Wednesday.
Detectives have released grainy CCTV and images of the suspects, who all wore black clothing with hi-vis vests and face coverings, in their bid to track them down.
They call for anyone who recognises any of them to come forward and want to speak with anyone in the areas at the time or who saw suspicious activity.
Federal police are assisting the investigation after Prime Minister Anthony Albanese labelled the billboard graffiti "terrorist propaganda" and community leaders lamented the normalisation of hatred being directed at Jews.
"This event has been devastating for the Jewish community and Victoria Police is fully committed to finding those responsible," Detective Acting Sergeant Travis Jones said.
"This behaviour has zero place in society, with Victoria Police and the (Australian Federal Police) working hand in hand to locate and charge the culprits."
October 7 marked two years since 1200 people were killed and about 250 hostages were taken from Israel in an attack by Hamas.
A total of 198 hostages have been returned to Israel, 148 of them alive.
The attack triggered an Israeli military campaign that has killed more than 66,000 people in Gaza, according to Palestinian health authorities.
Synagogues, schools and other buildings in Australia have been the target of vandalism and arson in the past two years, while Islamophobic incidents have also risen.
The Australian government angered Israeli Prime Minister Benjamin Netanyahu after joining like-minded allies such as Britain, France and Canada in recognising Palestinian statehood in a global push towards a two-state solution.
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