The NiceHash cryptocurrency website said in a press release on Wednesday night that it has suffered a security breach that compromised its digital wallet, which is believed to contain millions of dollars in bitcoins.
"The contents of the stolen NiceHash Bitcoin wallet We are working to verify the exact number of captured BTCs," the company said in a statement posted on Reddit.
The site had been inactive for hours so NiceHash initially said it was maintenance. As the interruption went on during the day, speculations turned on social networks that their digital wallet had been pirated.
"Although the full extent of what happened is not yet known, we recommend, as a precaution, that you change your passwords online," the site told users.
Bitcoin exchanges are often the target of cyberattacks and have been victims of high-profile theft in the past.
Such attacks can cause the value of the currency to collapse, although the falls are usually short-lived.
Bitcoin exceeded the $ 16,000 mark on Wednesday.
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