Australian authorities arrest 4 in alleged airplane terrorist plot

Authorities in Australia foiled a terrorist plot to bring down an airplane and arrested four men Saturday, Australian Prime Minister Malcolm Turnbull announced at a news conference Sunday in Sydney.

Police said it was an Islamist-inspired plot, but they did not link the plan to a specific terrorist group.

Australian Federal Police Commissioner Andrew Colvin said officers became aware people in Sydney were allegedly planning to carry out a terrorist attack using an "improvised device."

Turnbull said it was an elaborate conspiracy that involved bringing down an airplane.

The investigation is ongoing, officials said. Police did not specify the date or location of the threat to Australia's aviation industry.

The suspects are in police custody but have not yet been charged, Colvin said.

"Exactly what is behind this is something that we will need to investigate fully," he said.

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