Bitcoin's blockchain technology is, in principle, anonymous but also trackable due to the element of transparency. Therefore, Bitcoin can be referred to as “pseudo-anonymous”. Government agencies are hiring cryptocurrency experts to help them with BTC tracking and identity verification. There are different types of cryptocurrencies; the one most commonly traded, including bitcoin, is digital money that is not backed by any government.
It exists in a decentralized network of computers based on a technology called blockchain and protected by unbreakable codes. Taken literally, these facts could be interpreted to mean that law enforcement has found some way to decipher the encryption of bitcoin wallets. This is highly unlikely, if not simply false. Tracking bitcoin wallets is difficult, but it's not beyond the resources of law enforcement.
It's largely about using the public ledger and comparing dates and amounts. If a tracked wallet is found in a friendly jurisdiction, it can be seized by court order. But taking possession of the wallet is not synonymous with decrypting the key and recovering the contents. In proactive crime-fighting cases, police track down criminals.
When the offender exploits an unknown victim, the police can notify the victim of the crime regardless of whether the victim knows they were exploited or not. The police may be tracking certain cryptocurrency wallets or addresses, which may lead to a suspect behind the transactions. New advances in digital technology also allow researchers to view transactions to follow the virtual traces of money and reveal evidence about people who commit crimes. The men were caught converting their bitcoins into euros in bank accounts using Bitcoin trading services and then withdrawing millions in cash from ATMs.
However, with knowledge of the location of bitcoin, the wallet's key, and a court order, the FBI had everything it needed to open the wallet and seize the bitcoin.