More than 200 people have been arrested in 31 countries, including Ireland, as part of a global crackdown on money laundering by Europol.
The swoop by law enforcement authorities in European countries, as well as Australia and the United States took place between September and November.
It resulted "in the identification of 3,833 money mules alongside 386 money mule recruiters, of which 228 were arrested," Europol said in statement.
"More than 650 banks, 17 bank associations and other financial institutions helped to report 7,520 fraudulent money mule transactions, preventing a total loss of €12.9m", the statement said.
Money mules, unlike their drug-trade counterparts, are not moving illicit goods over a physical border.
Instead, they take part - often unknowingly - in money laundering activities by receiving and transferring illegally obtained money between bank accounts or countries.
