Crypto exchange Bitget has confirmed unauthorized transfers affecting approximately $351.6 million in assets and temporarily suspended withdrawals as it investigates the security breach.

Bitget said its security systems detected the transfers involving a limited number of hot wallets at 18:31 UTC on Thursday, prompting the exchange to activate emergency response procedures.

Bitget CEO Gracy Chen said the breach was contained to a portion of the exchange’s hot and warm wallet layers, while its cold wallets remained secure.

Speaking in a live Q&A, Chen said affected assets included Ether (ETH), XRP (XRP), USDt (USDT), USDC (USDC), Avalanche (AVAX), BNB (BNB) and USDT0 (USDT0) on Arbitrum. She identified Ethereum, the XRP Ledger, Avalanche, BNB Smart Chain and Arbitrum as affected networks, with Ethereum accounting for the main concentration of observed stolen funds.

Early onchain reporting captured a smaller amount than Bitget subsequently disclosed. Chen said this was because the incident extended beyond the Ethereum activity captured in early onchain analysis.

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Withdrawals have been temporarily suspended while the exchange conducts a security review. Chen said she expects withdrawals to reopen in a matter of hours or days.

Meanwhile, Bitget said it has flagged addresses associated with the transfers and contacted law enforcement and onchain security firms.

The exchange said user account balances remained accurate and that deposits and trading continue to operate normally.

Chen said affected funds are more than covered by Bitget’s User Protection Fund, which currently holds more than $464 million. She said the exchange would provide hourly updates and publish a full incident report, including a root-cause analysis and corrective actions, within 24 hours.

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