Police disrupt plot in Australia to ‘bring down an airplane’

Police disrupted the first alleged plot in Australia to bring down an airplane and arrested four men in raids on Sydney homes, officials said Sunday.

Prime Minister Malcolm Turnbull said that security has been increased at Sydney Airport since Thursday because of the plot. The increased security measures also were extended to all major international and domestic terminals around Australia overnight.

“I can report last night that there has been a major joint counterterrorism operation to disrupt a terrorist plot to bring down an airplane,” Turnbull told reporters. “The operation is continuing.” Australian Federal Police Commissioner Andrew Colvin said details were scant on the specifics of the attack, the location and timing.

“In recent days, law enforcement has been become aware of information that suggested some people in Sydney were planning to commit a terrorist attack using an improvised devise,” Colvin said.

Deakin University security expert Greg Barton said the first plot to target aircraft in Australia, which is the highest aspiration of many extremists, was a “pretty big threshold moment.”

The plotters were apparently making a peroxide-based explosive device rather than using nitrate-based chemicals that can be detected by airport security swab tests, Barton said.

Manchester Arena bomber Salman Abedi used such a peroxide-based explosive, triacetone triperoxide, better known as TATP, to kill 22 concertgoers in Britain on May 22.

There was no evidence that airport security had been compromised, Colvin said.

“We believe it’s Islamic-inspired terrorism,” Colvin said when asked if the Islamic State group was behind the plot.

None of the four suspects arrested in five raids had been charged, Colvin said.

He would not discuss what charges they might face. None of the arrested men worked in the airport industry, Colvin said.