Since 2015, U.S. intelligence agencies have seized more than $102 million in illicit digital currencies in 254 cases of cryptosphere crimes, CNBC writes.

According to investigators, stolen bitcoins and other digital currencies are converted into stablecoins.

Agents and analysts are actively tracking the flow of bitcoins and other cryptocurrencies on the blockchain, generally conducting financial and cybercrime investigations.

If you trace a digital currency wallet, it is not unlike an email address that has multiple correlating identifiers, and once someone makes a transaction, it goes into the blockchain, investigators have the ability to track that email address or wallet address through the blockchain. Cryptocurrencies such as bitcoin and Dogecoin are most represented on the blockchain.

Despite the significant expansion of the cryptosystem, reputable institutions such as the IMF, which are also beginning to utilize the innovation, are urging investors to exercise caution.

Among the majority of crimes in the cryptosphere, according to statistics collected by intelligence agencies, were such as placing false advertisements on popular online auctions and luxury goods websites that don’t actually exist, as well as delivering invoices purportedly from reputable companies to give the impression that the transaction was real. The criminals then implemented a money laundering scheme in which the victims’ funds were converted into digital assets.

Intelligence agents recognize that one of the features of cryptocurrencies is that when they are used, money moves faster than in the traditional format, and this fast pace of transactions makes the currencies attractive to both consumers and criminals. Criminals only wish to muddy the waters and make efforts to obfuscate their activities. Investigators, on the other hand, need to track their transactions as quickly as possible.

In order to track criminal activity, they have to monitor the market, because criminals are human too and want to avoid the market volatility associated with some of the major cryptocurrencies.