An alleged terror plot to bring down a plane in Australia may have involved the same chemical at the centre of the Manchester Arena bombing, a leading terror expert has suggested.
Federal police have spent days rifling through several properties across Sydney following the arrest on Saturday afternoon of four men on suspicion of being behind the conspiracy.
Authorities have only confirmed the plot involved an improvised device and the target was a plane, however one theory to emerge is that the men planned to use a meat grinder to conceal their home-made device.
Professor Greg Barton, a terrorism expert from Deakin University, said the suspects may have been directed by handlers in Syria.
“My speculative guess is they were probably trained in how to prepare TATP,” he told AAP.
The chemical, which was used in the Manchester Arena bombing in May and also in Paris in the 2015 attacks, is unstable but can be powerful when placed in a pressure vessel.
Prof Barton said it also didn’t produce “tell-tale” signs picked up at airport swab tests and would have appeared opaque under an X-ray.
“There’s a chance if someone had a hand-turned sausage grinder that’s not electric, it was packed so it didn’t rattle, and had a plausible story that they were asked to bring it back as a gift, that might just be plausible enough for it to slip through.”
While Prof Barton said the conspiracy was “clearly the most sophisticated terror plot” Australia had ever seen, it likely would have failed because the bomb may have been stopped at security, failed to detonate or failed to bring an aircraft down.
Meanwhile, Etihad Airways on Tuesday confirmed it was helping Australian authorities with the investigation amid reports the arrests were made after a tip-off from foreign intelligence services.
News agency Reuters cited a US official as saying the plot was “fairly well along”.
The four suspects remain in detention and can be held for up to a week as police gather evidence.