Bangkok — Thailand's Department of Special Investigation (DSI) has revealed that a Chinese 'grey capital' network laundered more than $300 million annually using a combination of illegal crypto mining and cash mules. The operation, which the DSI described as sophisticated and multi-layered, channeled funds through unregistered mining farms and then into the traditional financial system via human couriers. The announcement comes as Southeast Asian regulators increasingly target underground banking linked to Chinese capital flight.
How the scheme worked
According to the DSI, the network set up illegal crypto mining facilities — likely in remote areas or industrial zones — to convert cash into freshly minted coins. Mining, by its nature, generates new cryptocurrency without leaving an obvious paper trail. Once the coins were produced, the group moved them through a series of wallets before cashing out. To move the fiat proceeds, they relied on cash mules who physically transported money across borders, often in small amounts to avoid detection. The DSI did not specify how many individuals have been arrested or whether any mining sites have been shut down.
The 'grey capital' label
Chinese authorities and regulators frequently use the term 'grey capital' to describe money that is not strictly illegal but flows outside official channels — often to evade currency controls, taxes, or scrutiny. In this case, the DSI said the network was explicitly tied to Chinese nationals operating from Thailand. The scale — over $300 million per year — suggests the operation had been running for a while and had developed reliable logistics for both mining and cash transportation.
What happens next
The DSI said it is continuing its investigation and coordinating with relevant agencies. It did not name any specific exchanges or financial institutions involved, leaving open questions about whether Thai banks or crypto platforms were knowingly or unknowingly used in the process. For now, the case highlights a pattern that regulators across the region are watching closely: the intersection of crypto mining, cross-border cash couriers, and Chinese capital moving through Southeast Asia's less regulated financial corners.
