While the Biden administration is all hands on helping Ukrainians fight for their freedom, ours is getting challenged here at home.

Credit card companies like Visa, Mastercard, and American Express have moved to add a new subsection of the merchant code for retailers who are selling guns. Merchant-category codes (MCCs) are used to tag and identify the types of merchants using their platforms and the goods and services they sell. The three companies announced that gun retailers will be moved out of the “specialty retailers” or “durable goods sellers” categories and have their own section. These card networks said they would work with the authorities and abide by the guidelines for consumer privacy as they start rolling out these new codes.

One of the biggest supporters of this move, and a contributor to the Democratic letter from congress asking for a more stringent process on gun buying, Sen. Elizabeth Warren, said the code will be “an important step towards ending financial system support for gun trafficking, gun violence and domestic terrorism.”

Attorneys general of New York and California supported the motion and asked card networks to begin tracking gun sales and flagging suspicious activities, and forwarding them to law enforcement. The attorneys general cited the networks’ availability when reporting fraudulent activities that could be tied to money laundering and other kinds of criminal activity, so tracking gun sales should not be that hard.