US Homeland Security has accused Costa Rica-based online bookmaker 5Dimes of instructing US sports bettors to use Amazon gift cards to fund their online betting accounts.

In a seizure warrant filed with the US District Court in Philadelphia, the Department of Homeland Security (DHS) sought the seizure of 15 Amazon accounts that DHS investigators claim are linked to 5Dimes.

The warrant claims the accounts currently hold a combined $159k but allege that nearly $1.9m has passed through these accounts in the past few years. Re/code reported that Amazon has shut down one of the accounts, which was listed under the name GC Lover.

DHS says 5Dimes has been using the cards “in violation of Amazon’s terms of service” to facilitate payments to and from US sports bettors. The warrant alleges that 5Dimes paid out winnings to US bettors via the gift cards, or via merchandise the customers selected from the Amazon.com site.