Frydenberg slams Albanese over anti-Semitic attacks

Former treasurer Josh Frydenberg has accused Prime Minister Anthony Albanese of failing to set red lines not to be crossed after anti-Semitic attacks began ramping up in Australia.

The former Liberal party deputy leader said the discovery of a caravan containing explosives and addresses of Jewish targets was just the latest in a long list of incidents that have left the Jewish community less safe.

"The Jewish community - and it's about only 116,000 strong - is very scared. People are afraid to send their kids to school. People are afraid now to gather at places of worship," he told the ABC's 7.30 Report on Thursday night.

Mr Frydenberg, who is Jewish, said he was personally "cautious and extra vigilant" after receiving "very serious threats" that he had referred to federal police.

He said anti-Semitism had gained a foothold in Australia and from the beginning the prime minister "should have set red lines that were not to be crossed" to make sure culprits were arrested, convicted and punished.

"Because of the absence of action those who hate and those who harm have been emboldened."

Mr Frydenberg said he backed a coalition call for minimum mandatory sentences for those who commit terror attacks.

Rabbi Zalman Goldstein, who heads the Maroubra Synagogue in eastern Sydney, said his congregation was feeling defiant amid a rising tide of anti-Semitism and would not allow fear to take hold.

"The Jewish community is saddened to see this happening in Australia, and at the same time, the community is very strong and resilient - we don't get deterred or intimidated by bullies," he told AAP.

"Our strength comes from thousands of years of Jewish perseverance and survival. We've been through a lot.

"We're not going to allow fear to take hold."

He thanked authorities for swiftly responding on Thursday after more racist slurs were plastered near Mount Sinai Jewish school in Maroubra and two other properties in surrounding suburbs.

He also expressed relief a potential terrorist attack had been foiled.

A massive, multi-agency probe that includes counter-terrorism investigators was launched when an explosive-laden abandoned caravan was found on a semi-rural road in Sydney's northwest outskirts.

There was no detonator alongside the explosives but notes containing addresses of Jewish targets were also found in the caravan.

NSW Police Commissioner Karen Webb said the investigation was at a "delicate stage" with officers going through the physical evidence at the crime scene.

"But in terms of tracing where the explosives might have come from ... there's a fair bit of work to do yet," she told ABC Radio Sydney on Thursday.

NSW Premier Chris Minns described the find as a "potential terrorist event".

"I'm not a prophet but it's a great sign that police are finding more success and stopping them (perpetrators) in their tracks," Rabbi Goldstein said.

Rising tensions exploited by disruptive agitators have resulted in the defacing and bombing of synagogues, childcare centres and homes in Melbourne and Sydney.

Israeli Foreign Minister Gideon Saar said the foiled attack was another "intolerable" addition to a growing list of hate crimes.

"The epidemic of anti-Semitism is spreading in Australia almost unchecked," he posted on X.

"We expect the Australian government to do more to stop this disease."

ASIO Director-General Mike Burgess said in a statement that while he understood community fears and frustrations, the threat level would remain the same.

"While the caravan matter in New South Wales remains under police investigation, ASIO does not believe there is an ongoing threat to public safety."

He said the current threat designation of probable was the same as it was at the height of the Islamic State.