Thousands of protesters marched through the eastern Chinese city of Ningbo on Sunday demanding that the government halt the expansion of a petrochemical project which they feel will harm the environment.
Authorities ordered a crackdown amid reports of locals clashing with the police and damaging official vehicles during the protests which have continued through the last week.
The expansion is planned to be built in the Ningbo Petrochemical Economic and Technical Development Zone in the Zhenhai district in Zhejiang province with a combined investment of nearly 55.8 billion Yuan ($ 8.8 billion).
This is the latest in the several cases of localised civilian unrest where residents have opposed industrial projects over pollution fears across China.
Similar protests, the state media admitted last week, have erupted in several other cities in recent years. In 2007, thousands of people in east China's city of Xiamen protested the construction of a paraxylene (PX) plant over health concerns. The plant was eventually relocated.
Last year, authorities in northeast China's city of Dalian ordered a PX chemical plant to shut down after local residents took to the streets to demand that the plant be relocated over concerns regarding possible toxic chemical leaks.
Similar protests have also been reported in the cities of Chengdu, Nanjing and Qingdao.
The protests in Ningbo come at a time when the government least wants it as the Communist Party of China (CPC) readies for the 18th National Congress beginning on November 8.
Rioting erupted amid rumours that police had beaten to death a local college student -- a rumour police immediately denied. “Those people circulating fabricated rumours that 'police have beaten to death a college student' have had an odious social impact," Zhenhai police said in a posting on their microblog site.
On Saturday the protests spread to the center of Ningbo city, whose officials oversee Zhenhai. Agencies quoted residents as saying that Saturday's protests involved thousands of people and turned violent after authorities used tear gas and arrested participants.
The government blocked online searches of words like Ningbo and protests in Zhejiang as reports and photographs of the rapidly spread across social networking sites in China.
The government seems to be aware about the reasons behind such unrest.
“The public's awareness of environmental issues and their rights is increasing at a rapid pace," and the government should strive to “establish an open and transparent decision-making mechanism, and build a tolerant environment for public opinion,” said the influential CPC mouthpiece, People’s Daily.
The People's Daily said the growing frustration surrounding pollution from industrial projects provides the country with an opportunity to shift away from low-end manufacturing towards less-polluting industries.