Police say overseas and local criminals are suspected of working together in the firebombing of a synagogue in Melbourne last year.
They arrested one of three men they allege carried out the arson attack.
A 21-year-old Werribee man was arrested in Melbourne's west during one of multiple search warrants carried out around the city on Wednesday. The man is yet to be charged.
Two buildings belonging to the Adass Israel synagogue at Ripponlea in the city's south-east were destroyed in December 2024, with the fire attack forcing two congregants inside preparing for morning prayers to flee the building.
Australian Federal Police deputy commissioner Krissy Barrett told reporters she expected more people to be arrested in the future.
AFP deputy commissioner Krissy Barrett (left) said there could be more arrests in the future. Source: AAP / Rachael Ward
"The motivation is still being assessed and we will make further comments at an appropriate time about that," Barrett said.
An AFP officer involved with the 21-year-old's arrest is in hospital after being bitten by an unrestrained dog, which has since been euthanised.
Members of the Five Eyes intelligence alliance, as well as other international partners, have been involved in the investigation.
Victoria Police deputy commissioner Wendy Steendam said there was no evidence to suggest any links between the Adass Israel synagogue fire and a long-running criminal war over illegal tobacco in Melbourne or a separate fire at an east Melbourne synagogue.
Steendam also ruled out a connection to the discovery of a caravan in Sydney with explosives and a list of addresses of Jewish people, which was later determined by NSW Police and AFP to be a hoax.
"I want to reassure Victorians, particularly those in the Jewish community, that we remain relentless in our pursuit in finding all those responsible for this crime and holding them to account," she said.
Police executed seven search warrants across Melbourne on Wednesday, seizing various items, including electronic devices, which will be forensically examined.
In July, a 20-year-old man was arrested and charged over his alleged role in stealing a car linked to the Ripponlea synagogue fire.
There had been mounting pressure for police to make further arrests, with CCTV footage released by counter-terror police showing three people in hoodies getting out of a car before police claim they damaged the synagogue's entrance.
Investigators have urged anyone with further information about the car to come forward immediately.
Daniel Aghion, president of the Executive Council of Australian Jewry, thanked police for their efforts and hoped further arrests would be made.
"Only then will a deterrent be established against this sort of chilling behaviour."
