More than 15,000 Australian credit cards equating to some $3.75 million were salvaged from underground hacker forums under a global police sting.
The cards were held across 36 carding websites which used automated vending carts to sell the accounts in large batches.
Law enforcement agencies including the Australia Federal Police, the FBI, and the Netherlands national police force investigated the sites and on Wednesday they pounced.
Two men were arrested on suspicion of making large-scale purchases of compromised data from the carding sites, while British anti-fraud police seized computers suspected of being involved in the fraud racket. An operator of an automated vending cart was arrested in Macedonia.
The British serious organised crime unit (SOCA) claimed to have saved some $800 million through its anti-fraud efforts.
It said some two million pieces of financial and personal information have been seized by SOCA.
Details on the 15,450 compromised Australian cards found by the AFP since October last year were supplied to local banks.
The targeted carding websites now display a message from the US informing readers that the domain was seized.
One of the siezed sites.
“This operation is an excellent example of the level of international cooperation being focused on tackling online fraud,” SOCA head of cyber operations Lee Miles said.