Hundreds of heavily armed Australian police raided homes in Sydney and Brisbane before dawn, launching a the largest "counter-terrorism operation" the country has ever seen.
It comes just days after the country raised its threat levelto high for the first time.
Australian police said the raids were focused on suburbs in Sydney's northwest, while local media reported raids were also taking place in the Queensland city of Brisbane
Joint AFP/NSWPF operation underway – a number of arrests #sydneyarrests pic.twitter.com/se6PBcKIzO
— NSW Police (@nswpolice) September 17, 2014Last week, Australia raised its terror threat level to 'high', citing the likelihood of terrorist attacks by Australian citizens radicalised in Iraq or Syria, despite stressing there was no knowledge of a specific threat.
Australia, which is due to host the Group of 20 Leaders Summit in Brisbane in mid-November, is concerned over the number of its citizens believed to be fighting overseas with Islamist militant groups.
Up to 160 Australians have either been involved in the fighting or actively supporting it, officials say, and at least 20 have returned to Australia after fighting in the Middle East.
