The Financial Conduct Authority (FCA) and other UK authorities shut down eight sites across London as part of a crackdown on illegal peer-to-peer crypto trading, the agency announced on Wednesday. 

The FCA, which conducted the operation with HM Revenue & Customs and the South West Regional Organised Crime Unit, said it gathered evidence for ongoing criminal investigations and issued cease-and-desist letters at each site ordering traders to discontinue illicit activity immediately. The action was taken under the UK’s anti-money laundering and counterterrorism financing regulations, the agency said.

“Unregistered peer-to-peer crypto traders operating in the UK are doing so illegally and pose a financial crime risk,” said Steve Smart, executive director of enforcement and market oversight at the authority, in a statement. “Consumers should protect themselves by only dealing with firms registered with the FCA and by remembering that crypto remains a high-risk investment.” 

Although the agency characterized the action as the first of its kind against peer-to-peer crypto traders, the FCA has previously targeted unregistered cryptoasset activity, including prosecuting an individual who ran an illegal network of crypto ATMs and working with the Metropolitan Police to arrest two individuals linked to an illegal cryptocurrency exchange. 

Wednesday’s announcement comes as the FCA is poised to assume greater responsibility overseeing UK firms for anti-money-laundering and financial-crime compliance. 

That the authority has coordinated this latest action indicates that it is willing to do more than just make statements, Imogen Makin, counsel ⁠at law firm WilmerHale in London, told Reuters

“It seems likely that we will continue to see similar crackdowns in future as ⁠the FCA remains focused on combatting the risks associated with crypto and financial crime,” Makin said in the Reuters report

Read more from the FCA here