German investigators worked with law enforcement agencies from across Europe to smash a €100 million online trading scam, police announced on Tuesday.

A Bulgarian-based crime group created fake trading platforms for obscure financial instruments and cryptocurrencies, telling victims that the investments were safe and any major losses would be insured.

Victims were allegedly shown impressive earnings results to encourage further deposits, or, in the case of losses, were encouraged to further investment to cover the losses.

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Read more: Spanish police bust fake credit card ring, arrest 9/11 financier

Meanwhile, the network allegedly funneled the proceeds into companies that laundered the money. The group operated call centers, websites and software companies to facilitate the scam, police said.

Police said the network used social media and other techniques to lure victims across Europe before defrauding them of €100 million ($114 million) annually.

Austrian investigators said the platforms run by the group included: XTraderFX, Optionstars, OptionstarsGlobal, Goldenmarkets, SafeMarkets and Cryptopoint.

Read more: Vietnam crypto scam prompts crackdown on digital currencies

Austrian authorities were the first to uncover the scam, but much of the network's infrastructure was in Bulgaria and the Czech Republic.

A key suspect was detained during raids of 21 companies in Sofia, along with the seizure of a six-figure sum of money and several terabytes of data.

Austrian Interior Minister Herbert Kickl congratulated the international collaboration: "This successful action is an important blow against cybercrime, where perpetrators have access to state-of-the-art digital technology."

aw/amp (AFP, dpa)

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