New York: Hackers have stolen over $400,000 worth of cryptocurrency as they broke into the digital wallet of Stellar Lumen, one of the most popular virtual currencies in the world, according to media reports. The hackers on Saturday hijacked the server that hosts BlackWallet, a web-based wallet application that stores lumens, and stole 669,920 from users' accounts, the BBC reported. Although BlackWallet tried to warn users about the attack via forums, many continued to log in and lose money, the report quoted tech news site Bleeping Computer as saying. The stolen amount has been moved to Bittrex, a virtual currency exchange, where it was likely to be converted into another currency to hide their tracks, the site claimed. BlackWallet's creator, in a Reddit post, said he had since disabled his hosting account and websites. "I am sincerely sorry about this and hope that we will get the funds back. I am in talks with my hosting provider to get as much information about the hacker and will see what can be done with it," the developer, who goes by the alias of Orbit84, said.