Japanese cryptocurrency exchange DMM has suffered a cyber attack resulting in the loss of over $305 million in Bitcoin. The breach, which occurred on May 30, saw hackers steal 4,502.9 Bitcoin by compromising the exchange’s server security. DMM has assured users that their deposits are safe and has taken full responsibility for the stolen assets.

In response to the attack, DMM has temporarily suspended several services, including withdrawals, new account creations, new spot buy orders, and new leveraged orders, although pre-existing limit orders remain unaffected.

The cyber attack generated significant discussion among crypto enthusiasts on social media, especially after Whale Alert, an analytics platform, reported a large Bitcoin transfer of 4,502 Bitcoins from an unknown wallet to an unidentified destination. DMM later confirmed the loss.

DMM is taking measures to prevent future unauthorized outflows and plans to compensate users by procuring an equivalent amount of lost Bitcoin through its group of companies. The exchange has advised users to stay vigilant for updates and will notify them once normal services resume.

Owned by e-commerce giant DMM Group, DMM exchange has been operational since January 2018 and also runs a crypto mining firm. This incident highlights the ongoing risk of cyber attacks on cryptocurrency exchanges, with similar breaches occurring in the past, such as Poloniex losing over $100 million in November and GDAC losing $14 million in April 2023.