HUIZHOU, Guangdong - Police in Guangdong have unearthed the province's biggest-ever case of marked industrial oil smuggling, involving a whopping 6 billion yuan ($879 million), local media reported on Tuesday.

Tan Qiang, 40, and his youngest brother, who was not named, are suspected of masterminding the smuggling outfit, and were arrested earlier this year at their villa in Aotou, a coastal township of Huizhou, the Guangzhou-based Southern Metropolis Daily reported.

Tan and his gang allegedly smuggled more than 200,000 tons of marked industrial oil, commonly known as red oil in South China, valued at about 6 billion yuan, into China from Hong Kong and other countries, it said.