An application for a seizure warrant filed recently by a Department of Homeland Security investigator in the U.S. District Court in Philadelphia alleges Amazon gift cards were used by the operators of an offshore gambling website to launder nearly $2 million over the past few years.

The filing alleges that in an attempt to bypass the U.S. financial system’s controls on gambling transactions U.S. customers were instructed by the Costa Rica-based gambling site to fund their 5Dimes sports betting accounts using Amazon gift cards. According to the feds, U.S. customer’s winnings were also paid out in Amazon gift cards, or in merchandise they chose on Amazon.com.

The document reads, “[T]he investigation has determined that 5Dimes has developed an alternative to the traditional online financial payment methods, which is unavailable to 5Dimes under federal law, in order to operate its illegal betting operation in the U.S.,” and, “This illegal alternative relies on the use of [Amazon gift cards], in violation of Amazon’s terms of service,” according to re/code.

The case is made by the Homeland Security warrant application for a total of $159,000 to be seized, which is currently spread among 15 accounts on Amazon believed to be tied to 5Dimes. Amazon accounts bearing names such as GC Lover and Blue Iguana have held close to $1.9 million in combined funds over the years. According to the filing, the GC Lover account has been shut down by Amazon.

Bettors are not charged a fee by 5Dimes if their accounts are funded with Amazon gift cards. Bettors have been instructed by the company to purchase these gift cards in cash from traditional retail stores and along with a receipt email a photo of the card information. Bettors are also offered a 10 percent bonus by the gambling site if they choose to receive their winnings via gift cards from Amazon added to their Amazon account. The application says gift cards were also used by the company to purchase merchandise such as 50 custom sweatshirts with the 5Dimes logo and 100 office chairs.

According to 5Dimes website, the company was established in San Jose, Costa Rica, and its first casino was launched in November of 1996.