Among those detained is the director of PNJ Laboratory Company Limited (PNJ-LAB), a subsidiary of Vietnam's largest listed jewelry company, Phu Nhuan Jewelry Joint Stock Company (PNJ), authorities announced on Thursday.

Police escort suspects in a diamond smuggling case. Photo by VnExpress/Lam Son

Police in Thanh Hoa Province in central Vientam had coordinated with Ho Chi Minh City colleagues to conduct raids at 20 locations, including jewelry stores and the residences of those involved, last month.

The operation yielded 1,100 seized diamonds, along with transaction records, electronic data, and storage devices. Investigators determined that the ring had smuggled and sold the stones in Vietnam, generating an estimated revenue of VND280 billion (US$10.7 million).

The network was allegedly orchestrated by several Indian nationals based in Hong Kong. Diamonds were initially sourced from India, gathered in Hong Kong, and illicitly transported into Vietnam.