Police said suspects conspired with the Islamic State militant group and were also trying to build a device designed to release poisonous gas in a public area.
Two men have been charged in Australia over a plot “inspired and directed” by the Islamic State militant group to place a home-made bomb on an Etihad Airways flight, authorities said on Friday.
Police said the high-grade military explosives used to build the bomb were sent by air cargo from Turkey. The device was disguised as a commercial meat mincer and taken to a check-in counter at Sydney airport on July 15 – but it never made it past airport security.
“This is one of the most sophisticated plots that has ever been attempted on Australian soil,” Australian Federal Police Deputy Commissioner National Security Michael Phelan told a news conference.
The suspects, who have been charged with terror-related offences, were arrested in raids across Sydney last week.
They were also trying to build a separate device designed to release poisonous hydrogen sulfide gas in a public area, police said. Chemicals and other components were found in the raids but the accused were “a long way” from making a functioning device.
Hydrogen sulfide, which smells like rotten eggs, is deadly in high concentrations.
Police said “preliminary and hypothetical” discussions between the accused and ISIL suggested a plan to deploy the chemical device in a crowded place, such as public transport.
Police allege that one of the two men charged late on Thursday (August 3) had been introduced to ISIL by his brother, who they said was a senior member of the group in Syria.
Communication between the suspect and ISIL began around April, and under the instruction of a senior ISIL commander, he and the second suspect built a “fully functioning IED” (improvised explosive device).
On July 15, one of the men, an Australian, sent his unsuspecting brother to Sydney airport to catch an Etihad Airways flight carrying the device – disguised as a commercial meat mincer – in his luggage.
Police say the brother “had no idea” he was carrying a bomb in his luggage.
What happened next remains unclear, but police said it appeared one of the accused left the airport, taking the luggage with him, while the brother boarded the plane and has not since returned to Australia.
Police arrested four men last weekend in raids across Australia’s biggest city of Sydney. One man has been released while another is being held without charge under special counter-terror laws.
Etihad said in a statement on Friday it had been working closely with the Australian Federal Police investigation.