Hackers have emptied a digital wallet belonging to the cryptocurrency company NiceHash, leading it to shut down its website Wednesday, according to Business Insider.
The hack affected NiceHash's payment system and hackers got away with the contents of its bitcoin wallet, it wrote in a Facebook post.
"Clearly, this is a matter of deep concern, and we are working hard to rectify the matter in the coming days," NiceHash said in the Facebook post. "In addition to undertaking our own investigation, the incident has been reported to the relevant authorities and law enforcement, and we are cooperating with them as a matter of urgency."
While NiceHash did not release details on how much bitcoin had been stolen or how much of what was stolen belonged to its customers, some of its customers estimated that around 4,736 bitcoin were taken, which would be the equivalent of $63 million as of Wednesday afternoon or $77 million by Thursday morning.
Users arrived at the estimate by looking at the total amount sitting in a recently created bitcoin wallet, which are publicly searchable online, though the owners of which are usually kept anonymous.
Blockchain, the technology behind bitcoin and other cryptocurrencies, is widely regarded as safer and more secure than other digital financial transactions, but the hack on NiceHash marks the second cryptocurrency startup to suffer a major hack in recent months. Parity, a digital wallet that collects millions in fundraising, saw $162 million of the cryptocurrency ether frozen when a hacker deleted code necessary to access funds stored in some of its users' digital wallets, according to Business Insider.
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