Against growing tensions after China positioned a giant oil rig in an area also claimed by Vietnam, rioting broke out in industrial parks in Vietnam. Vietnamese mobs targeting Chinese companies set fire to foreign-owned factories and rampaged through industrial zones in the south of the country. The protests were initially peaceful but broke down when the number of protestors grew. The brunt of the rioting appears to have been borne by Taiwanese firms mistaken for Chinese firms in the Binh Duong and Dong Nai provinces.

One of the companies affected include Taiwan’s largest investor in Vietnam, Formosa Plastics Group. FY Hong, President of Formosa, has been reported to have said about 300 rioters looted the company’s factory premises. He also said the Dong Nai complex generates about US$660 million a year and that Formosa would rethink about investing further in Vietnam. "The Vietnamese government's inability to stop rioters from pillaging foreign companies is raising major concerns, and it may hurt the country's appeal to international investors,” he said.

Last year, Formosa had said it planned to invest US$500 million in its textile and BOPP production facility; with US$100 million to build a factory for 200,000 tonnes of polystyrene/year.

Other companies affected by the rioting include Malaysian furniture manufacturer Latitude Tree Holdings as well as three Singaporean factories that were also reported to have been ransacked at two Vietnam-Singapore joint venture industrial parks in Binh Duong. Other companies like Hong Kong public-listed sports shoe maker Yue Yuen, which supplies footwear to Adidas and Nike, said it had suspended production.

News reports say that dozens of ships from both countries are around the oil rig, and the two sides have accused each other of intentional collisions. China’s Foreign Ministry spokeswoman Hua Chunying told reporters that China was seriously concerned about the violence and has "demanded the Vietnamese side make efforts to adopt effective measures to resolutely support eliminating illegal criminal acts and protect the safety of Chinese citizens and institutions.” China has laid its claims on almost all of the South China Sea area, which is an important passageway for ships and rich in energy deposits..

Other Asian countries like Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims on the area.