GUANGZHOU, Jan. 8 (Xinhua) -- Five oil-smuggling rings were busted on Tuesday in southern Guangdong Province, with 46 suspects seized, the customs department of the city of Guangzhou announced.

The gangs, involved in smuggling about 200,000 tonnes of refined oil, worth about 700 million yuan (102 million U.S. dollars), were busted in a joint operation of Guangzhou Customs, Guangdong coast guard and customs officers of other cities.

Six vessels were confiscated, and four oil storehouses were sealed up, local customs said.

A gang led by a suspect surnamed Cai caught the attention of customs officers earlier. Investigation showed that the gang had connections with oil suppliers in Taiwan and other oil smuggling rings in Guangdong. The rings have transported refined oil products from Taiwan to the international water south off Guangzhou and smuggled them with smaller vessels into the Pearl River Delta area and east Guangdong to store and sell.

The case is under further investigation.