Tether froze more than 4.5 million USDT linked to Mercado Bitcoin’s Nov. 2 security incident, as the Brazilian exchange suspended deposits and withdrawals while investigating suspicious fund movements. Summary Tether CEO Paolo Ardoino confirmed the freeze of more than 4.5 million USDT. Mercado Bitcoin said it contained the incident, with no customer harm or data breach. Deposits and withdrawals were temporarily suspended while the exchange investigated and tracked affected assets. The exchange published destination addresses across five blockchain categories to support tracking efforts. Tether CEO Paolo Ardoino announced the freeze while sharing Mercado Bitcoin’s official statement about the breach. His announcement provided a specific amount of USDT blocked in connection with the incident, following reports of suspicious outflows exceeding $40 million. “Tether froze more than 4.5M USDT related to this security incident,” Ardoino wrote. The announcement described a freeze, without saying the tokens had been returned to Mercado Bitcoin. The exchange’s own updates focused on containing the incident, tracing assets and restoring operations safely. Mercado Bitcoin suspends transfers after containing breach In its initial statement, Mercado Bitcoin said it identified and swiftly contained a security incident affecting one of its systems early that morning. The exchange said customers suffered no harm and that there had been no data breach. It described the temporary suspension of deposits and withdrawals as a precautionary measure taken to protect the platform while its teams investigated. Mercado Bitcoin said those teams were tracking assets and coordinating measures with the relevant authorities. Its statement did not describe a customer reimbursement process, consistent with the company’s assertion that customers had not suffered losses. In a subsequent update, the company said it continued working to restore operations safely and would keep customers informed through official channels. The update maintained the focus on recovery work and asset tracking without announcing that deposits or withdrawals had reopened. For customers, the operational restriction therefore remained separate from the exchange’s assurance about their balances: Mercado Bitcoin said customers had not been harmed, while transfers into and out of the platform were temporarily unavailable. Exchange shares addresses across five blockchain categories Mercado Bitcoin’s follow-up published destination addresses identified in transactions related to the incident, covering EVM-compatible networks, Bitcoin, Solana, Stellar and Tron. The company said it was releasing the addresses to contribute to monitoring and tracking assets on blockchain networks. It specified that the list was disclosed exclusively for identification and tracking purposes. Its EVM entry identified the address 0xe485e7A70b1131216Cb47CA4555c4Bbb2C742478. Separate entries listed destinations for BTC, SOL, XLM and TRON, giving investigators and other market participants references for following transactions associated with the breach. The disclosure did not assign a dollar value to each destination or identify how much of the affected assets sat on each network. Ardoino’s announcement likewise did not allocate the frozen USDT between the published addresses. Brazilian outlet BitNotícias reported that security company Hypernative had flagged more than $40 million in suspicious transfers from wallets attributed to Mercado Bitcoin. According to that report, the movements involved newly created destination addresses across at least 10 blockchain networks. The reported outflow estimate and Tether’s freeze cover different measures: one concerns suspicious transfers across multiple assets and networks, while the other identifies USDT blocked by its issuer. Neither announcement established a final recoverable total. Hypernative had already joined Brazil’s monitoring push Hypernative’s reported alert follows earlier work involving the company and Brazil’s financial sector. As crypto.news reported in August, Brazil’s central bank had developed a real-time crypto threat monitoring and alert-sharing system with Hypernative. Mercado Bitcoin and Foxbit were among the exchanges named as participants in its planned integration. The project was designed to distribute warnings between banks and crypto companies when suspicious funds moved through the financial system. Testing had been completed, with participating organizations preparing their systems to receive and redistribute alerts. That earlier report described the monitoring project’s development and intended participants. Mercado Bitcoin’s Nov. 2 statements described its own investigation and coordination with authorities, without identifying which alert-sharing infrastructure was used during this incident. Tether’s US enforcement work shows its freeze process Tether has previously described asset freezes as a way to prevent further movement of funds linked to suspected unlawful activity. In an April 23 announcement, the issuer said it supported US authorities in freezing $344 million USDT across two addresses after receiving information about alleged unlawful conduct. At that time, Tether said it worked with more than 340 law enforcement agencies across 65 countries. Its disclosed cooperation included more than 1,200 cases tied to US law enforcement. For the Mercado Bitcoin incident, the exchange said its teams were continuing asset tracking and working to restore operations, with further updates to be issued through its official channels.
