Five California residents were arrested at the request of the Federal Republic of Germany for an alleged fraud scheme involving fake recurring card charges from phony merchants, U.S. officials announced on Wednesday.

The suspects allegedly organized a scheme where they deliberately kept the monthly charges below €50 to avoid suspicion among victims, according to German authorities.

The five men, four of them U.S. citizens, were identified by authorities as Medhat Mourid, of Woodland Hills, Andrew Garroni, of Los Angeles, Guy Mizrachi, of Agoura Hills, Ardeshir Akhavan, of Irvine, and Canadian National Tunde Benak, of Irvine.

The men are accused of scamming thousands of victims out of more than €300 million, which resulted in the creation of a “shadow financial system” in Germany, authorities said.

“The operators of the network then colluded with German payment service processors – including their executives and compliance officers – to process these payments,  Former employees and executives of German payment processors are among those arrested yesterday,” wrote the DOJ in a press release.

The U.S. Marshals Service arrested the Southern California residents and said they would extradite the men to Germany at the request of the country after making their initial federal court appearances on Wednesday.