Jin's operation was based in China, and he used encrypted communications and cryptocurrencies to conduct his business. The investigation involved a team of agents from various federal agencies, including the DEA, FBI, and IRS, who worked together to gather evidence and track down Jin's associates in the US. One of these associates, Bin Wang, was arrested in 2017 and later sentenced to six years in prison. The team discovered that Jin was using a company in Tonga to ship his packages, and that he was offering a wide range of synthetic opioids, including carfentanil and U-48800. As the investigation continued, the team found that Jin's operation was linked to numerous death cases across the US, and that he was using his websites to sell drugs to customers in the US. The team eventually identified Jin as Fujing Zheng, a 35-year-old man from Shanghai, and his father, Guanghua Zheng, who was 62. The Zhengs were found to be operating a sophisticated online drug trafficking operation, using encrypted communications and cryptocurrencies to conduct their business. Despite the evidence gathered, the Chinese government refused to extradite the Zhengs to the US, citing a lack of evidence. The US government eventually indicted the Zhengs and shut down their websites, but they remain at large in China. The investigation highlighted the challenges of combating online drug trafficking, particularly when it involves foreign nationals and jurisdictions.

deal to distribute fentanyl in China, which marked the beginning of China's ability to produce fentanyl.