Take it away, SCMP:
More than a thousand people gathered in the eastern Chinese port city of Ningbo on Saturday to protest against plans to expand a petrochemical plant, highlighting a major challenge for the leadership as it readies for its once-in-a-decade power transition.
On Friday, protesters overturned a police car and attacked the police.
By early Saturday, protesters, watched over by police, gathered in a central shopping street in Ningbo, wearing masks and giving out pamphlets denouncing the expansion of the plant by a subsidiary of China Petroleum and Chemical Corporation in the district of Zhenhai.
Ningbo is a big city, and the protests seem to basically take the form of the 'mass urban stroll' seen in other environmental protests in Dalian and Qidong recently, except that they confirm a trend towards limited violence seen in the latter protests: cop cars were overturned and tear gas used. However, the protest as a whole wasn't a mass riot against real or perceived injustice on the classic mass incident model and the authorities have convened some kind of forum to discuss the protestors' grievances.
Perhaps surprisingly in view of the upcoming leadership handover, discussion of the affair has been permitted across the Sinosphere, though attempts to post photos from the scene are apparently blocked. You can see some over here.