BitMart confirmed a hack in an official statement, labeling it a “large-scale security breach” and reporting that the hackers withdrew about $150 million in crypto assets. But, blockchain security and data analytics firm Peckshield estimated the stolen amount be close to $200 million.

The intruder breached Ethereum and Binance wallets with a flood of transfers which began at around 2:30 pm Eastern Time on 4th December. The initial hack was followed by an exodus of tokens two hours later, including USDC and Shiba.

Sheldon Xia, the founder of BitMart, said only a tiny percentage of BitMart’s assets were at risk. Nonetheless, the company still froze withdrawals until further notice and is thoroughly reviewing security.

Peckshield was the first to see the breach on Saturday, noting that one of BitMart’s addresses showed a steady outflow of tens of millions of dollars to an address which analytics platform Etherscan referred to as the ‘BitMart Hacker.’

It is unclear who hacked BitMart, but the culprit seems to be knowledgeable. The stolen funds have been sent to an Ethereum mixing service that makes tracking the funds difficult. Crypto thieves aren’t usually astute. While this is not the biggest crypto heist, cryptocurrency news-site CoinDesk notes that this is one of the more prominent centralized exchange hacks to date.