State media blamed villagers for inciting the violence in Guangdong province. There were unconfirmed reports that a teenage girl died in the clash and that the village of Panlong was sealed off.
Telephone calls late Monday to the Sanjiao township and Zhongshan city, which both oversee Panlong, were not answered. The lack of information is typical in a country where the communist central government tightly controls information.
However, in a rare and swift acknowledgment of unrest in the countryside, the official Xinhua News Agency late Sunday cited a local official as saying police had not used force to disperse villagers.
The report, which contained an unusual amount of detail, said the crowd threw rocks and firecrackers at policemen, which "led to chaos."
It said two policemen and three villagers were injured, and police cars were smashed.
Saturday's incident came a month after authorities fired into a crowd of villagers in Dongzhou, also in Guangdong, reportedly leaving up to 20 dead.
The protests in Dongzhou and Panlong — like many protests elsewhere in China's impoverished countryside — focused on complaints of inadequate compensation for farmland seized by authorities for industrial use or property development. Government figures show there were 74,000 cases of rural unrest in 2004.
On Wednesday, more than 50 petitioners from Panlong gathered in front of a government office to complain about compensation for 320 acres of land the local government confiscated in 2003, Xinhua said. The number grew to over 100 Saturday, the agency said. Protesters also blocked a highway.
"The municipal police bureau sent policemen to help maintain traffic order that night, who then were attacked by villagers," Xinhua said, citing an unidentified spokesman for Zhongshan.
The protests have alarmed communist leaders, who are promising to spend more to raise living standards in the countryside, home to about 800 million people.