The incident stands as one of the largest hacks in the digital asset industry in recent years.

On Friday, around 1:30 pm local time, DMM Bitcoin detected the unauthorized transfer of 4,503 BTC from its wallet, equivalent to $308 million at the time. The exchange has not yet disclosed the specifics of how the hack transpired but stated that it is currently investigating the matter and implementing measures to prevent future attacks.

Decrypt reached out to DMM Bitcoin for additional information but has not received a response at the time of reporting. The company, however, has assured its customers that it will continue to guarantee all BTC deposits despite the exploit. As a precautionary step, DMM Bitcoin has temporarily halted spot trading purchases, the opening of leveraged trading positions, and the screening of new account openings. Crypto withdrawals have also been suspended, although Japanese Yen withdrawals are still permitted with potential delays.

This recent hack stands as one of the most significant incidents in the cryptocurrency sector, surpassing any major breaches recorded in 2023 or this year. However, 2022 witnessed a series of notable hacks targeting various layer-1 blockchains, sidechains, crypto exchanges, and DeFi protocols. Notably, the BNB Chain hack amounted to $566 million worth of BNB, making it the largest hack of that year.

In Japan, this incident marks the second-largest crypto-related hack in history, following the 2018 raid on Coincheck, where hackers stole over $550 million worth of XEM, a peer-to-peer cryptocurrency.

DMM Bitcoin is actively cooperating with authorities to investigate the breach further and enhance security protocols to prevent similar incidents in the future.