It’s not just your wallet, watch or Louis Vuitton purse that thieves have their eye on now.

As the popularity of bitcoin skyrockets across the globe, crooks have pivoted to getting their hands on your virtual currency as well. Six-figure holdups have become routine now, according to a New York Times report, with one Russian tourist being blindfolded and forced to transfer $100,000 in bitcoin last month while in Thailand.

The relative obscurity of cryptocurrency transactions — payments are sent to digital “wallets” that correspond to a lengthy numerical address, rather than a username — adds an extra layer of protection for the perpetrators. It also makes returning the stolen money to the victims a tall task.

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“For this, the advantage of bitcoin is that it’s hard to verify,” a Thai police investigator told the Times. “We asked the victim how to track it since they know bitcoin better than us. We asked them how to check the receiver. They said there is no way. It is hard to do.”

Similar attacks have become more commonplace. Weeks earlier, the head of a bitcoin exchange in Ukraine was held hostage for $1 million. In December, a man in New York City was kidnapped by a “friend” until he forked over a $1.8 million ransom in Ether, the second-most popular cryptocurrency. And last fall, a Turkish businessman was forced by an armed gang to give away his passwords to his digital wallets — with the thugs making off with about $3 million in cryptocurrency.

The rise in cryptocurrency prices in the last year has been followed by a spike in cryptocurrency robberies, and many “crypto rich” people are still grappling with how to best protect their investments. Some have set up a “duress wallet,” or small lump of money, to throw perps off the scent of their bigger nest egg. Others, like Jameson Lopp, told the Times they’ve set up security cameras and bought automatic weapons to safeguard their investment.

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“If you are rich and you own real estate, or stocks or a sports team, somebody can’t mug you and take your sports team away,” Lopp told the Times. “Having liquid crypto assets makes you much more attractive for that type of criminal attack.”

Read the full NYT report here.