Tether, the issuer of the USDT stablecoin, and crypto exchange OKX have partnered with the U.S. Department of Justice to seize $225 million, the largest-ever freeze of USDT in history, according to a Nov. 20 statement.

The frozen USDT was linked to an international human trafficking syndicate in Southeast Asia that orchestrated a global “pig butchering” romance scam. Per the statement, the funds were locked in multiple self-custodied wallets linked to the criminal group.

The freezing occurred following an investigation facilitated by Chainalysis, a blockchain analytics firm. Tether and OKX collaborated by notifying the DOJ and other law enforcement bodies about the illicit fund movements, leading to the DOJ’s request to freeze the wallets involved.

Tether clarified that the frozen wallets aren’t directly tied to its customers and asserted the legality of the freeze. The firm also committed to working with law enforcement and the wallet owners to resolve the situation.

This development aligns with recent efforts by crypto-related entities to deter unlawful fund transfers through cryptocurrencies. Earlier, Tether froze 32 addresses holding $873,118.34 connected to illicit activities in Israel and Ukraine. Additionally, the company has seized around $835 million in assets, primarily associated with thefts and other unlawful activities.

Paolo Ardoino, CEO of Tether, emphasized the firm’s stance against illegal crypto usage, adding that the company aims to establish higher safety standards in the crypto sphere. Ardoino further stressed the importance of technology and collaborations to combat unlawful activities proactively.

Similarly, OKX’s Chief Innovation Officer, Jason Lau, highlighted the exchange’s commitment to partnering with law enforcement and industry stakeholders to foster trust and contribute to public welfare. Lau affirmed OKX’s proactive involvement in such initiatives in the future.

Over the past year, Tether has emerged as the undisputed leader in the stablecoin space, with its circulating supply at nearly 88 billion and a market dominance of 70%, according to CryptoSlate’s data.