Eighteen Australians are facing criminal charges after a global money-laundering sting that stopped $2.6 million in "dirty cash" flowing through the nation's financial institutions.
The Australian Federal Police operation identified 27 alleged money mules, people who are used by criminals to transfer money, usually cash from the proceeds of crime.
Two were allegedly the head of money-laundering organisations, the AFP said on Tuesday.
Eighteen people were charged by NSW, Queensland, Western Australia and Victoria police, while nine warning letters were issued telling people to cease activities suspected to be associated with money laundering.
Australian police, financial analysts and cybercrime experts were part of the worldwide operation that included law agencies from 27 countries and ran from mid-September to the end of November.
It stopped $2.6 million "washing through" Australia's financial institutions, the AFP said.
More than 1800 people were arrested globally.
AFP cybercrime commander Ben Case said criminals used a rage of tactics to convince people to launder money, including romance and job scams.
"International students are a common target of money mule networks. However, this is a warning to everyone: if it sounds too good to be true then it probably is," he said.
"If you're being promised a pay cheque for simply moving money between accounts, converting money to cryptocurrency and moving it to another wallet, or an online romantic partner is asking you to transfer funds on their behalf, then it is more than likely a scam."
Victoria Police cybercrime detective Jane Welsh said organised criminals sought people with legitimate Australian bank accounts to move money from a compromised account out of the country.
"Unfortunately, the reality is that people transferring these funds are money mules, and these scams are a cover for criminals' money-laundering efforts," she said.
"The funds that people are being asked to move are the proceeds of other criminal thefts, such as those facilitated by business email compromise, false invoices or confidence scams.
"Money mules, even unsuspecting ones, should understand that they are complicit in serious crimes, and will be targeted accordingly."
The European Union's law enforcement agency said nearly 7000 fraudulent financial transactions were uncovered during the 2021 sting.
This seventh joint operation prevented losses totalling 67.5 million euros ($A107 million), it said.
Australian Associated Press