A Nigerian citizen has been accused of executing a multi-million dollar email scam at a Sydney immigration center.
The 43-year-old man is among the four people arrested and charged by the alleged union in New South Wales.
The police claim that he was the ringleader and that he used 16 mobile phones and 17 different sim cards to coordinate the scam from the Villawood detention center.
The union was allegedly involved in a variety of fraudulent activities, including romance scams, identity theft and commercial e-mail engagements, defrauding the Australians by more than $ 3 million.
Detective Superintendent Arthur Katsogiannis said investigators believe the money was sent to Nigeria.
He said it was "highly unlikely" that the funds would ever recover.
"We can not establish at this time who is being targeted or what is being used (for)," he told reporters in Sydney on Friday.
"We are working with our international colleagues in complying with the law to establish what happened to that money."
The Nigerian man was accused of deliberately directing activities of a criminal group, two charges of knowingly dealing with the proceeds of crime and possessing identity information to commit an incriminating offense.
He must appear at the Bankstown Local Court later on Friday.
A 36-year-old woman, as well as a 20-year-old man and woman, were also arrested and charged with various crimes.
Everyone must face the local Parramatta court on October 2.
Det Supt Katsogiannis urged Australians to be extremely careful when giving away information online, pointing out the emotional and psychological impact that scams can have on people, as well as on finances.
"People committed suicide after losing their life savings," he said.
"It's costing taxpayers millions of dollars each year, not only in Australia, but around the world, and that's why it's important to identify these people."
The investigations continue and new arrests have not been ruled out.