The German Attorney General's Office Frankfurt am Main (Generalstaatsanwaltschaft) and the country’s Federal Criminal Police Office (BKA) have shut down 47 crypto exchanges allegedly tied to criminal activities including money laundering.

The exchanges purposefully failed to comply with their obligation to carry out certain identity and background checks on their customers, also known as “know your customer” (KYC) requirements, the BKA said in a press release on Thursday.

Some of the exchanges include Xchange.cash, 60cek.org, Baksman.com, alongside other smaller platforms. One of the exchanges had been active since 2012 while others had launched as recently as the previous year.

Some customer and transaction data was seized by the government in the process of the investigation, it said. Given that the people behind those activities often reside in other countries outside of Germany, where criminal activities like this are “tolerated or even protected,” the authorities noted it may be nearly impossible for German government officials to prosecute them.

Instead, they will focus on “weakening” the underlying infrastructure that allowed for those illegal activities, according to the statement.

Earlier this year, the BKA seized 49,857 bitcoin (BTC), worth $2.1 billion at the time, from the operators of a privacy website called Movie2k.to, which was shut down in 2013 for violating the Copyright Act.

The agency proceeded to sell the tokens in July, causing distress in the global crypto markets due to the selling pressure resulting from the dump as well as the simultaneous repayments by defunct bitcoin exchange Mt. Gox, which happened around the same time.