US authorities including the FBI have indicted 17 people accused of money laundering and credit card fraud worth hundreds of thousands of dollars.
The defendants are accused of using stolen card data from Europe to carry out large cash withdrawals from ATMs in Chicago.
According to the 29 count indictment, two Bulgaria-based defendants fraudulently obtained European card numbers and PINs, which were then sent via e-mail and Skype to the Bulgarian gang leader based in Chicago.
The stolen data was then encoded on to magnetic strip cards that were handed out to the defendants who withdrew cash from ATMs around Chicago, circumventing withdrawal limits by taking cash out before and after midnight.
The FBI arrested 13 defendants in the Chicago area at the end of March 2014, with a further two arrested in Bulgaria who now face possible extradition to the US.
The FBI has reportedly been following the group over the past three to four years in collaboration with Bulgarian Prosecution and the Bulgarian State Agency for National Security.