https://motherboard.vice.com/en_us/article/ne4xdk/a-cryptocurrency-theft-bigger-than-mt-gox-just-happened-in-japan-coincheck-nem

A Japanese cryptocurrency exchange says it just experienced what may be the most financially damaging marketplace theft in the history of the technology.

The sum allegedly stolen from the Coincheck exchange—500 million units of NEM, a newer cryptocurrency—was worth roughly $500 million USD at the time of the theft, which would eclipse even the alleged 2014 hack of Japanese exchange Mt. Gox. That incident saw $450 million USD worth of Bitcoin go missing and embroiled founder Mark Karpeles in a legal drama that is still ongoing nearly four years later. According to Japanese newspaper Asahi, Coincheck has alerted police to the theft.