Cyber-terrorism has been identified as an emerging threat by a US terrorism expert visiting Australia.

Speaking on Channel Seven, Matthew Devost from the Terrorism Research Centre in the United States defined cyber-terrorism as a sustained attack on critical infrastructure, such as telecommunications or financial infrastructures.

He warns an attack on such infrastructure would have a lasting impact on society, particularly if it followed a physical terrorist attack.

“With regard to Al Qaeda to having the capability, our belief is that they don’t currently have the capability to have that sustainable impact,” Mr Devost said.

“There is a big difference between hacking a website on the Internet and taking the power down.

“However, given their resources and given what we have seen with regard to some of the capabilities of individuals within the group, they could acquire that capability,” he said.