The nation’s spy boss has issued a chilling warning about a growing risk of foreign governments trying to murder dissidents in Australia as he warns that social media algorithms and artificial intelligence are fuelling a disturbing rise in radicalisation.

In a sobering speech to the Lowy Institute think tank in Sydney, Australian Security Intelligence Organisation (ASIO) director-general Mike Burgess said the nation was facing an unprecedented number of simultaneous threats to social cohesion, including Russian trolls, neo-Nazis, Islamists and extreme anti-Israel activists.

Hours before Burgess’ speech, NSW Police arrested 13 anti-Israel protesters rallying outside a maritime conference and weapons expo in Sydney’s Darling Harbour, where two Israeli defence companies were exhibiting their equipment.

Declaring that community cohesion in Australia is “under siege, under threat, under attack”, Burgess said the nation’s social fabric is “fraying in ways we have never experienced before”.

“Australia has never faced so many different threats at scale at once,” he said.

Warning that intolerance is rising and anti-authority beliefs proliferating, Burgess said: “There are multiple, cascading and intersecting threats to our social cohesion, fuelled by three distinct but connected cohorts: the aggrieved, the opportunistic and the cunning.”

Burgess said that national security and law enforcement agencies were facing “a domestic security environment with an unprecedented number of challenges, and an unprecedented cumulative level of potential harm”.

ASIO has said since 2022 that foreign interference and espionage, rather than terrorism, is the nation’s principal national security threat.

“Given the degrading trajectory of our security environment and the growing willingness of regimes to conduct high-harm operations, ASIO assesses there is a realistic possibility a foreign government will attempt to assassinate a perceived dissident in Australia,” Burgess warned.

“This threat is real. We believe there are at least three nations willing and capable of conducting lethal targeting here.”

Burgess did not name the three countries, but said it was possible foreign governments would try to hide assassination attempts by using “criminal cut-outs” as Iran did in its arson attacks on a Jewish synagogue and a kosher deli in Melbourne and Sydney respectively.

“Regimes are operating in a security grey zone using non-traditional tools to interfere in decision-making, promote discord, amplify distrust and spread false narratives in Western democracies,” he said.

“Authoritarian regimes demonstrate a chilling willingness to exploit fault lines in countries they consider hostile.”

Burgess said that “state-sanctioned trolls” – especially from Russia – were trying to sow discord in Australia by attempting to “hijack and inflame legitimate debate”.

“We recently uncovered links between pro-Russian influencers in Australia and an offshore media organisation that almost certainly receives direction from Russian intelligence,” he said.

While the attempts so far have only gained limited traction, he said: “I am deeply concerned about the potential for AI to take online radicalisation and disinformation to entirely new levels.”

Burgess said that war in Gaza had not directly inspired terrorism in Australia, but it “prompted protest, exacerbated tension, undermined social cohesion and elevated intolerance”.

Since the October 7 attacks of 2023, Burgess said the nation had seen “a notable uptick in intentionally disruptive and damaging tactics by anti-Israel activists, including multiple acts of arson, vandalism and violent protest against defence companies accused of supplying weapon components”.

He referred to a group posting a video threatening “consequences” for the employees of an unnamed business.

“Every worker in this supply chain is complicit,” the video stated. “We will decide your fate as you have decided the fate of millions … We have been closely watching you. We have your addresses. Stop arming ‘israel’ [sic] or else…”

Meanwhile, he said that neo-Nazis had used anti-immigration rallies to raise their profile and fuel grievance in Australia.

While the National Socialist Network has not engaged in terrorism, Burgess said: “I remain deeply concerned by its hateful, divisive rhetoric and increasingly violent propaganda, and the growing likelihood these things will prompt spontaneous violence, particularly in response to perceived provocation.”

Burgess said he was also worried about Islamist group Hizb ut-Tahrir, which infiltrated the university encampment and pro-Palestine movements, as this masthead reported last year.

Hizb ut-Tahrir is listed as a terror group in the United Kingdom but not in Australia.

Burgess said he fears the group’s “anti-Israel rhetoric is fuelling and normalising wider antisemitic narratives”, adding that its “provocative behaviour, offensive rhetoric and insidious strategy are very similar to the tactics of the National Socialist Network”.

“The organisation’s condemnation of Israel and Jews attracts media attention and aids recruitment, but it deliberately stops short of promoting onshore acts of politically motivated violence,” he said.

Burgess, who has given several high-profile speeches since becoming head of ASIO in 2019, was reappointed to a second five-year term last June.

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