As the prices of cryptocurrencies experienced a meteoric increase last year, so did the number of thefts involving various types of digital currencies. Capitalizing on the rise of Bitcoin and other altcoins, thieves are beginning to shift their targets from the conventionally wealthy to the digitally rich.

In December, kidnappers in Ukraine abducted an employee at a United Kingdom-registered cryptocurrency exchange and demanded over $1 million in Bitcoins as ransom. Pavel Lerner, one of the top analysts and blockchain experts in the firm, was forcefully taken by six balaclava-clad men armed with guns on Dec. 26. Fortunately, Lerner was released after EXMO, the company he was working for, paid the seven-digit ransom.

A few weeks later, history repeated itself in Phuket, Thailand. A few armed assailants forced their victim, a young Russian man into his own apartment and locked him there, blindfolded. They then made him log into his computer and transfer $100,000 worth of Bitcoin into an unknown online wallet before letting him go.

In New York, a man was held captive by an associate, who demanded him to transfer $1.8 million worth of Ether, the cryptocurrency on the Ethereum network. According to the New York County District Attorney’s report, the robber, a man named Louis Meza, scheduled to meet the victim in his car, where he “demanded that the victim turn over his cell phone, wallet, and keys while holding the victim at gunpoint.”

Meza then brought the victim back to the victim’s apartment, where the daily robbery took place. Below is an extract from the DA’s report:

“Video surveillance later obtained from the victim’s apartment building showed MEZA using the set of keys stolen from the victim to enter the victim’s apartment and then leave the apartment holding a box believed to contain the victim’s digital wallet. Additional records reveal that soon after obtaining the victim’s digital wallet, the defendant then transferred approximately $1.8 million in Ether to his own personal account.”

Why Virtual Currencies?

Because of their anonymity and the immutability of the blockchain, cryptocurrencies can be effectively transferred to the account of a robber without much hassle. Furthermore, since there is no middleman to facilitate or, in this case, halt a transfer, there is a huge chance that a robber can get away scot-free with a successful heist.

“This is now becoming more pervasive and touching more law enforcement divisions that deal with organized crime and violent crime on a local level,” said Jonathan Levin, the founder of Chainalysis, which has worked with several law enforcement agencies on virtual currency crimes.