A new service will give criminals a way to check how "clean" their digital currency is.
Dr Tom Robinson, chief scientist and founder at analysis provider Elliptic, who discovered the website on the darknet, has explained how the service works and how it can be exploited to the benefit of criminals.
He said: "We're seeing criminals start to fight back against blockchain analytics and this service is a first.
"It's called Antinalysis and criminals are now able to check their own Bitcoin wallets and see whether any association with criminal activity could be flagged by authorities."
Dr Robinson thinks the service underlines that cyber-crime networks are becoming increasingly sophisticated.
He reflected: "It's a very valuable technique. If your funds are tainted, you can then do more laundering and try to remove that association with criminal activity until you have clean coins."
Dr Robinson noted that the system isn't working very well for the time being. However, in time, he thinks it's set to change.
He told the BBC: "It actually wasn't very good at identifying links to criminal sites. However, it will inevitably improve over time. So I think this is going to be a significant capability for criminals and money launderers in the future."
