“It’s clearly designed to harm people, but it’s also designed to create fear in the community. And that is the very definition,” he said.

NSW Police found a caravan in Dural in Sydney packed with explosives — that had the potential to cause a “mass casualty event”. Source: AAP / Bianca De Marchi

NSW Police have not officially declared the incident as a terrorist act.

“I often get asked — and I want to clarify — about whether or not there needs to be a declaration of a terrorism event. That relates to whether there’s need for additional powers. That is separate to the issue of whether police can charge with terrorism offences,” she said.

Declaring an incident a terrorist event grants police extraordinary powers in NSW — police may search people’s properties without a warrant, demand the disclosure of people’s identities and establish a roadblock around a target area.

How is terrorism defined?

The acts or threats are “ideologically motivated” or “religiously motivated”.

The behaviour fits this definition if it “causes serious physical harm to a person or serious damage to property, causes death or endangers a person’s life, creates a serious risk to the health and safety of the public, or seriously interferes, disrupts or destroys an electronic information, telecommunications or financial system”.

The difference between a ‘terrorist act’ and ‘terrorism’

Unlike other Australian jurisdictions, in the Northern Territory, there is a specific offence of terrorism rather than a general definition of a ‘terrorist act’.

What does ASIO say?

“I understand how distressing these incidents are, and want to assure members of the community ASIO is using the full range of its capabilities to assist multiple police investigations, including through the well-established structures of Joint Counter Terrorism Teams around the country.”