Australia details Islamic State plot to take down plane

SYDNEY — The Australian police described on Friday an elaborate terrorist plot in which two men from Sydney tried to place an explosive supplied by the Islamic State on a flight last month, an operation that officials said was among “the most sophisticated plots that has ever been attempted on Australian soil.”

Officials said the discovery of the plot was the 13th significant threat that police had exposed and broken up since Australia raised its terrorist threat level to probable in 2014.

“The threat from terrorism is real,” Michael Phelan, the deputy commissioner of the Australian Federal Police, said at a news conference on Friday announcing the charges against the two men, Khaled Mahmoud Khayat, 49, and Mahmoud Khayat, 32.

Investigators say that parts of the explosive, a roadside bomb, were sent through international air cargo from Turkey through Islamic State operatives in Syria to one of the suspects in Australia, Phelan said.

Investigators also said that after the airport plot did not succeed, the suspects tried to create an improvised chemical device intended to release “highly toxic hydrogen sulfide.”