Operation Firewall was an an undercover investigation undertaken by the U.S. Immigration and Customs Enforcement (ICE) that targeted the full array of methods used to smuggle bulk cash, including commercial and private passenger vehicles, commercial airline shipments and passengers, and pedestrians crossing U.S. borders with Mexico and Canada.
It resulted in the arrest in 2004 of more than 28 members of the "Shadowcrew" criminal organization, located in eight states in the United States and eight foreign countries — the United Kingdom, Canada, Bulgaria, Belarus, Poland, Sweden, the Netherlands, and Ukraine.
Members of the group were later charged in a 62-count indictment with trafficking in at least 1.5 million stolen credit and bank card numbers that resulted in losses in excess of $4 million. As part of this takedown, the U.S. Secret Service disabled the Shadowcrew website. With the exception of two fugitives, all of the domestic Shadowcrew defendants pled guilty and received sentences of up to 90 months in prison.