Before the incident occurred, authorities stated that the national terror alert was set to “probable,” suggesting an equal likelihood of a terror attack happening in Australia.

But what does the term ‘probable’ signify for Australia?

Australia is currently operating under a terrorism threat level classified as probable.

According to the national terrorism advisory framework, a “probable” status signifies that “a terrorist attack is likely, and there are credible concerns about a potential threat” from the government’s perspective.

At the time the alert was elevated, Australians were informed that there is more than a 50 percent likelihood of an attack or related planning occurring within the country over the next year.

Under the national terrorism advisory system, probable is defined as “a terrorist attack is probable and the government has concerns of a plausible threat”.

When the alert level was raised, Australians were told there “is a greater than 50 per cent chance of an onshore attack or attack planning in the next 12 months”.

However, Prime Minister Anthony Albanese said a “probable” alert does not mean “inevitable”.

Why was the terrorism threat level changed?

At the time, intelligence experts said the decision to raise the threat level was not triggered by any single ideology or issue, but an overall rise in polarisation in Australia and other Western nations.

The terror threat level was last changed in 2022, when it was lowered to “possible”.

“The advice that we have received is that more Australians are embracing a more diverse range of extreme ideologies and it is our responsibility to be vigilant,” Albanese said in August last year.

“To be clear, this is the same threat level that was in place in Australia for more than eight years before it was lowered in November of 2022.

“At that time, we said as a government, it’s does not mean the threat from terrorism is extinguished.”

The national terrorism threat level is a warning tool to provide the government and the public an indication of what ASIO is seeing and anticipates in the near future.

Will the terrorism threat level change?

In the hours after the attack, Australian Security Intelligence Organisation (ASIO) Director-General Mike Burgess maintained the threat level would likely not change from “probable”.

“I don’t see that changing at this stage,” he said.

“One incident by itself does not necessarily raise the threat level at the national level, but we keep that under constant review.

Burgess confirmed investigations are ongoing into any other possible threats, after father and son Sajid and Naveed Akram were named as the shooters.

“We’re looking to see if there’s anyone in the community that has similar intent,” he said.

“It’s important to stress at this point, we have no indications to that fact, but that is something we have active investigations on.”