China's ambition to build a harmonious clean-tech economy lost some of its sheen on Sunday after a violent confrontation over pollution from a solar panel factory.

Riot police broke up a four-day protest by several hundred villagers in Haining, Zhejiang province, who overturned cars and stormed the compound of a photovoltaic manufacturer that is accused of releasing toxins into a local river.

The demonstrators complained of police brutality and efforts to silence their voices in the latest in a rash of rallies and protests over environmental concerns in China.
The target on this occasion was Jinko Solar Holding, a fast-growing company listed on the New York stock exchange that produces ingots, wafers, cells and modules.

Although solar is seen as clean energy in terms of carbon emissions, the production of many components is energy intensive and polluting. Toxic discharges from the factory killed large numbers of fish and regulators have previously ordered the company to suspend operations, according to the domestic media.

Chen Hongming, deputy head of Haining's environmental protection bureau, told the Xinhua news agency that the plant has failed to meet pollution standards since April despite official warnings.

Locals are frustrated their complaints have not been heard. On Thursday, 500 people burst into the factory compound. They were dispersed, but continued their protests by camping outside.

Photographs and video of the demonstrations have spread across the internet. One banner – shown on the website of the National Business Daily newspaper – reads: "Return our lives to us, stay away from Jinko."

Video images on the municipal website showed smashed factory windows. Eight company vehicles were overturned on Thursday and four police vehicles were damaged on the following days, according to official accounts.

Riot police dispersed the gathering on Sunday and sealed off the site. Witnesses complained to reporters that the security forces had used heavy-handed tactics.
"Some people were beaten up during the protests," a protester with the surname Cao told Reuters. "Why can't we just tell the truth about this pollution? Now people talking to reporters are also being detained: what justice is there? We are being silenced."

Villagers said they wanted the factory to move because they were worried about the impact of its discharges into the river and air on the health of their children.
The clash highlights the difficulty that China faces as it tries to clean up its environment, reduce its reliance on coal and secure "clean tech" export business. The country is the world's biggest manufacturer of solar panels with about 70% of the global market, but overseas rivals say this dominant position has been achieved through unfair subsidies, low wages and lax environmental regulation.

Increasingly, however, Chinese citizens are uneasy about the consequences of pollution in all industries. As incomes levels and environmental awareness rise, there is a growing reluctance to accept dirty growth. Last month, the Dalian city government promised to halt a planned paraxylene (PX) plant after a rally by tens of thousands of people. In recent years, there have also been several violent demonstrations against battery factories and smelting facilities that are blamed for unhealthy levels of lead in the blood of children in some area. Many other smaller protests in the countryside go largely unreported.