Update to this story

Australia accounts for the largest per capita number of foreign fighters in ISIS.

(AFP) – A series of anti-terror raids across Sydney and Brisbane were sparked by a senior Islamic State militant ordering “demonstration killings” in Australia, Prime Minister Tony Abbott said today.

“The exhortations, quite direct exhortations, were coming from an Australian who is apparently quite senior in Isil to networks of support back in Australia to conduct demonstration killings here in this country,” he said.

“So this is not just suspicion, this is intent and that’s why the police and security agencies decided to act in the way they have.”