Global information service group Experian may have compromised the data of millions of their customers after possibly becoming the targets of a Vietnamese con man.

According to reports, a Vietnamese man claiming to be a private investigator succeeded in gaining access to financial records of US consumers by purchasing them from a company owned by Experian. The information which was previously being safeguarded by one of the world’s largest credit monitors may now be sold illegally online for fraudulent purposes.

While it is not clear how many US citizens may have been affected by the illegal sale of their data, it is estimated that as many as 30 million credit records may have been sold in total. Experian senior VP of government affairs Tony Hadley stated that the company was unaware of the scam going on, stating that “We were a victim, and scammed by this person.”

The man behind this massive security leak is 24-year-old Hieu Minh Ngo, who was arrested by US Secret Service agents after selling off consumer information online.