Rioters in the western Chinese region of Chongqing burned police cars and looted government buildings after a quarrel between residents escalated into a riot involving thousands, residents and officials said.
The angry crowds gathered on Monday night during a quarrel between fruit market workers and a delivery boy, after one worker passed himself off as an official and threatened to use his rank to resolve the dispute in his favour, state media said.
That caused bystanders, angry at the attempted abuse of privilege, to become involved in the dispute. Residents said crowds grew to more than 20,000 after cars and buses passing through the area stopped to watch.
A report on the Web site of the Hong Kong newspaper Ming Pao said that, after the trouble flared, some 1,000 fully armed riot police intervened and, after fierce clashes with brick-throwing rioters, finally dispersed them with tear gas and rubber bullets. An official news report posted on the Wanzhou government's Web site (www.wz.gov.cn) said five were detained for burning and overturning police cars and stealing a computer from a local government building. It did not say what caused the disturbance.
A Wanzhou official said more than 10 had been detained.
"I heard some protesters burned police vehicles and police fired tear gas," said a hotel employee at the Changcheng Chang Hotel in Wanzhou district near the riot scene. China has seen mounting anger against abuse of privilege as the gap between rich and poor widens, with hundreds of millions of peasants left out of its economic boom.
A case last year in which a woman killed a farmer with her BMW but was let off with a suspended sentence attracted wide attention and the investigation was eventually reopened.
A Wanzhou police officer acknowledged there had been a "security disturbance" on Monday but declined to give details.
"A man carrying a pole hit a woman passing by and the two of them started an argument. The woman then called a man, who later arrived at the scene and beat and injured the man carrying the pole and even threatened to pay money to 'buy' his life," said the Web site article, monitored by the BBC.