The four suspects arrested in a series of raids by counter-terrorism police on Saturday in Sydney may have been planning to deploy a toxic gas on a passenger aircraft, incapacitating everyone on board and crashing the plane, according to a report in The Australian.
The group — two fathers men and their adults sons who are all related by marriage — was allegedly working on an “elaborate” plan to take down a plane and the sophistication of the plot has led authorities to believe they may have had direction from overseas.
Prime minister Malcolm Turnbull announced stricter security measures at all domestic airports on Sunday morning with immediate effect. Passengers are now being asked to arrive at terminals two hours before scheduled domestic departures and three hours before international flights to allow extra time for security screening.
Significant delays are expected at Australian airports today as a result of the new screening protocols.
The Australian reports that the four suspects “were constructing an explosive device that could have emitted a toxic, sulphur-based gas that would have killed or immobilised everyone on the aircraft.”
“It is understood the device was in the final stages of readiness, prompting police to swoop,” the report said.
Police carried out searches at five locations across Sydney on Saturday afternoon, seizing a range of items and arresting the four suspects.
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