Cryptocurrencies are of much concern to government authorities around the world for several reasons: they might undermine the standard of currencies issued by central banks, resulting in potential economic depressions worse than ever seen before; they're unregulated, which means activities involving cryptocurrencies could defraud investors of their personal wealth; and companies that issue cryptocurrencies could pull out and leave all owners of such digital currencies high and dry.

There's also one more concern - because some cryptocurrencies are untraceable, their use could inherently be tied to activity on black markets around the world.

According to Europol and Spain's Guardia Civil, 11 people were recently arrested for laundering money through cryptocurrencies to the tune of some 8 million euros.

A press release detailing such findings was released yesterday, on Monday, April 9, 2018, by Europol itself.

Here's what happened, more or less - those eleven newly-minted criminals would profit from the sales of drugs. With such profits, credit cards and cryptocurrencies would be used to transfer them throughout various countries in Europe, with those criminals eventually cashing out in various cryptocurrencies.

They would initially pick up such money in cash, then deposit them across tons of bank accounts in Europe in sums too small to be reported to authorities. Afterwards, those criminals tried their hardest - and succeeded, in large part - to launder such money back to Colombia, were various drugs were initially sourced from.

Criminals would take out credit and debit cards from various financial institutions - hundreds of cards between those eleven criminals - and do business with various causes. Once completed, such money would end up in the pockets of criminals in Colombia.

Bitcoin was used for most of the transactions, even though Bitcoin can be traced with enough effort put forth.

Together with law enforcement officers in Finland, Europol and Guardia Civil had collectively found those eleven criminals guilty. It's said that a whopping 137 others are currently being investigated by Spain's Guardia Civil regarding the money laundering issues.