Iran was behind at least two antisemitic attacks on Australian soil, ASIO believes, prompting the Australian government to sever diplomatic ties with the country.

Appearing in the prime minister’s courtyard on Tuesday, the spy agency’s director-general, Mike Burgess, said Melbourne’s Adass Israel Synagogue attack from last December and Sydney’s Lewis Continental Kitchen attack from last October were ordered by Iran and believed the country was behind further attacks.

“They put lives at risk, they terrified the community and they tore at our social fabric. Iran and its proxies literally and figuratively lit the matches and fanned the flames,” he said.

Prime Minister Anthony Albanese said Iran was responsible for “extraordinary and dangerous acts of aggression” and attempts to “undermine Australian cohesion”.

“The Australian people want two things. They want killing in the Middle East to stop, and they don’t want conflict in the Middle East brought here. Iran has sought to do just that,” he said.

“They have sought to harm and terrorise Jewish Australians and sow hatred and division in our community.”

Iranian ambassador to Australia Ahmad Sadeghi and three other officials have been expelled, with seven days to leave. Operations at Australia’s embassy in Tehran have been suspended, with all Australian diplomats already out of the country.

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Foreign Minister Penny Wong said it was the first time since World War II that Australia had expelled a foreign ambassador.

Iran’s Islamic Revolutionary Guard Corps (IRGC) will also be designated as a terrorist organisation, pending legislation.

Mr Burgess said the IRGC directed the attack through a series of “cut-outs” or third parties, and that some perpetrators were paid.

Links to offshore criminal gangs

He said no diplomats or embassy staff were involved, adding “offshore organised crime” was involved but that he did not believe any Australian criminal gangs were.

“It’s a layer cake of cut-outs between IRGC and … the alleged perpetrators conducting crimes. In between them, they tap into a number of people, agents of IRGC, and people that they know in the criminal world, and work through there,” he said.

The director-general said he briefed the government on the findings yesterday, which were the subject of a lengthy investigation.

“Formal assessments are not done quickly or taken lightly. Our analysts carefully weigh every piece of intelligence. Their conclusions are clear,” he said.

Asked about any future threats, Mr Burgess said law enforcement investigations had focused on past events but that he was confident authorities could stop any future attack they knew about.

Mr Burgess said ASIO was still investigating possible Iranian involvement in “a number of other attacks” but said he wanted to “stress we do not believe the [Iranian] regime is responsible for every act of antisemitism in Australia”.

Tony Burke, who is minister for home affairs and multicultural affairs, said the community should “stand together in unity and strength” and urged against blaming “Australians of Iranian heritage”.

“That is exactly the kind of disunity and division that these attacks were designed to create,” he said.