Thailand’s central bank is targeting crypto transactions as part of a broader crackdown on illicit finance.

Bank of Thailand Governor Vitai Ratanakorn said over the weekend that the bank and the country’s Securities and Exchange Commission are using data-analytics tools to audit abnormally high-volume trades in stablecoins such as Tether’s USDT, according to local news outlet Thansettakij.

Early reviews have already flagged transactions that appear structured to conceal ownership or move money outside normal banking channels, Ratanakorn said, according to Thansettakij. The central bank has handed those findings to the SEC, which holds direct statutory authority over digital assets in Thailand, for possible enforcement.

“The measures we are implementing are not short-term fixes; they require the continuous deployment of multiple parallel strategies,” Ratanakorn was quoted as saying.

The stablecoin audit is one strand of a broad crackdown on what Thai officials call the grey economy, the flow of suspicious cash across the region. Since April, anyone withdrawing 5 million baht (about $150,000) or more in cash has had to give their bank a commercial reason for it, a step the BOT credits with reducing large withdrawals by about 35%. From the fourth quarter, depositors bringing in the same amount may have to declare where the money came from. Regulators have also tightened reporting on gold trading, where monthly withdrawals fell from about 4,000 kilograms to 700, and closed thousands of accounts used as “mules” for online-gambling flows.

Thai police in collaboration with Interpol recently identified a romance-scam laundering network in which a single wallet allegedly controlled by a suspect aged 20 moved more than $122.5 million in 10 months.

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