Clashes with riot police broke out in south-western China last week after thousands of protesters besieged a government office, a human rights centre and a witness said on Monday.
Friday's incident in Chongqing city's Youyang county was sparked when relatives of a school student who had been stabbed to death by a schoolmate claimed they were beaten by police as they protested in front of the school.
The angry crowd then moved to the township government office, holding a banner saying "Murder in the School", a witness who was working at a hotel next to the office told Reuters. "More and more people gathered around the county government, and the whole street was jammed for hours," she said by telephone. The Hong Kong-based Information Centre for Human Rights and Democracy said the number of protesters was as much as 10,000.