Two Russian-born Australian citizens have been accused of obtaining Australian Defence Force material to share with Russian authorities.
Australian Federal Police arrested a 40-year-old woman, who is an ADF army private, and a 62-year-old man at their home in Brisbane in Everton Park on Thursday morning.
The married couple have been charged with one count each of preparing for an espionage offence, which carries a maximum penalty of 15 years' imprisonment.
It is the first time an espionage offence has been laid since foreign interference laws were introduced in 2018.
The pair are due to appear before Brisbane Magistrates Court today, where police will allege the woman undertook undeclared travel to Russia while on long-term leave from the ADF, where she allegedly instructed her husband on how to log into her work account and access material to send to her.
The couple had been in Australia for more than a decade before the alleged offending.
Police will allege the pair sought the information with the intention to provide it to Russian authorities - whether it was actually shared is still a subject of Operation BURGAZADA's investigation.
How someone with a security clearance was able to travel to Russia will also form part of the ongoing investigation.
Further spying charges could be laid
A more serious offence of espionage requires a direct evidential link to a foreign state, which carries penalties of 25 years to life in jail.
Police said further charges could be laid as the investigation continued.
AFP Commissioner Reece Kershaw said espionage offences were not victimless.
"It has the potential to impact on Australia's sovereignty, safety and way of life," Kershaw said.
Spy chief Mike Burgess said espionage was not a "quaint" notion and could have "catastrophic real-world consequences".
"Espionage is real. Multiple countries are seeking to steal Australia's secrets," Burgess said.
Burgess said he would not make further comment because the offences had not been tested in court.
The AFP and ASIO said there was no ongoing risk to the public.
The AFP will work with defence to determine whether there are additional security lessons for the ADF.
This story was first published by the ABC.