Chinese police have arrested eight people implicated in a smuggling case involving more than 34,000 tonnes of oil, local customs said on Wednesday.

More than 10 other suspects were detained and two tankers seized after customs police in east China's Jiangsu Province busted the ring, which has been operating since the end of 2013.

The smuggling ring bought oil from a Taiwanese tanker in open waters. A suspect set up a company in Dongying City, Shandong Province, to sell the oil.

The smuggled oil is worth about 250 million yuan (about 39 million U.S. dollars). The group evaded an estimated 68 million yuan in taxes.

In early 2015, customs officials in Yangzhou City, Jiangsu, started to suspect a tanker after discovering falsified application materials. Upon investigation, its Automatic Identification System devices, a system used to record data from ships' activities, were shut down.

Later, the police tracked the tanker, along with another. They found evidence of smuggling on the vessels, although the suspects had fled.

The suspects were caught in late March. The Taiwanese suspect was nabbed at the port of Xiamen, Fujian Province, in mid-July.