The federal government announced tougher security processes at all major Australian airports after police said they had foiled an alleged terror plot in Sydney on Saturday.
Since then, Australia has been hit by five terrorist attacks, including multiple stabbings and, notably, a shooting targeting New South Wales police that left one person dead.
"Investigators believe that, based on the degree of sophistication of the plot, the group may have had some overseas direction", the Sydney Morning Herald reported. Police said they found "a number of items of great interest" during the raids, but remained tight lipped on further details related to seized materials.
"As a matter of course, the Australian government will continue to monitor security developments and adjust security settings as needed", he said.
The precautions include additional checks of cabin and checked baggage at Sydney, Melbourne, Brisbane, Darwin, Hobart, Perth, Adelaide, Canberra, Cairns and the Gold Coast.
It's believed the four men were plotting to bring down an aeroplane using a homemade bomb.
The 2014 Lindt cafe siege in Sydney, in which the hostage-taker and two people were killed, was Australia's most deadly violence inspired by the so-called Islamic State.
The increased security measures also were extended to all major worldwide and domestic terminals around Australia overnight.
"The threat of terrorism is very real".
The plot involved smuggling the device onto a flight from Sydney to the Middle East, possibly Dubai, as carry-on luggage, the newspaper said.
There was no evidence that airport security had been compromised, Colvin said.
A woman led from a raid by police with her head covered told Nine Network Television: "I love Australia". "[Increased security measures] will be required for as long as the threat is assessed as requiring them".
The country's national terrorism threat level is still at "probable".
The plot was "Islamist-inspired", police said. If you would like to discuss another topic, look for a relevant article.
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