People in the south-western city of Chongqing fought riot police after a flower-seller was attacked by a policeman.
The rioting took place last weekend. It is currently unclear why the policeman attacked Mr Changming, but he was apparently hospitalised after being beaten with a shovel. His wife brother-in-law and son were also injured.
Rioting broke out shortly afterwards, with angry people surrounding police cars. Violent clashes broke out between roughly 1000 people and 100 riot police. In the course of eight hours of fighting two police cars were destroyed and 10 people were injured, four seriously.
Another flower-seller was beaten by city inspectors in Zhengzhou last week, this also lead to rioting with thousands facing up to riot police. This incident has reportedly led to the disciplining of several police officers and party officials.
Chongqing is the world's fastest growing conurbation and has been the site of violence before. In November 2005, police put 20 strikers in hospital while breaking up protest against lay-offs by 10,000 workers from a state steel factory. In 2004 there was massive rioting after massive job losses were caused by the Three Gorges dam project. Entire districts of the city were closed and moved with at least 47,000 jobs lost as a direct result.