FBI investigators announced this week that they have uncovered a global financial network run by members of ISIS who are utilizing fake eBay transactions to transfer money to one another.

Federal investigators arrested an American citizen residing in Maryland who had been receiving some of the funds in question under the FBI’s investigation:

The government had alleged in a 2016 indictment that the American suspect, Mohamed Elshinawy, pledged allegiance to Islamic State and had pretended to sell computer printers on eBay as a cover to receive payments through PayPal, potentially to fund terror attacks. The recently unsealed FBI affidavit, filed in federal court in Baltimore, alleges that Mr. Elshinawy was part of a global network stretching from Britain to Bangladesh that used similar schemes to fund Islamic State and was directed by a now-dead senior ISIS figure in Syria, Siful Sujan.

The alleged financial network through eBay has been used to buy military supplies. Some of the players in the network may have been killed in a December 2015 drone sweep, according to FBI documents. The same documents reveal that now-dead senior ISIS official Siful Sujan was one of the parties that participated in the underground financial network. The ring operated through a British technology company that Sujan founded.

A spokeswoman for PayPal, which facilitates transactions on the eBay platform, said that it “invests significant time and resources in working to prevent terrorist activity on our platform….We proactively report suspicious activities and respond quickly to lawful requests to support law enforcement agencies in their investigations.”

A spokesman for eBay said that the company “has zero tolerance for criminal activities taking place on our marketplace” and said that they are cooperating with law enforcement’s requests on the case.