BEIJING Chinese police are hunting protesters who went on the rampage at the weekend in a campaign against a huge waste incinerator, turning over and setting fire to police cars, state media reported on Monday.
Choking smog blankets many Chinese cities and the environmental degradation resulting from the country's breakneck economic growth is angering its increasingly well-educated and affluent population.
The demonstrations, which have run for more than two weeks, turned violent on Saturday, with hundreds of police descending on to the streets of Yuhang, close to the eastern tourist city of Hangzhou.
At least 10 protesters and 29 policemen were injured, more than 30 cars were overturned, two police cars set on fire and four more smashed up, according to state media.
The government says it will shelve plans to build the plant if it does not have popular support.
Eleven suspects involved in the violence had already turned themselves in and 53 had been detained, Hangzhou police said in a statement posted online, adding that they were urging others to surrender.
"For those who refuse to surrender, abscond or continue to carry out criminal activities, public security and judicial authorities will adopt forceful measures to bring them to justice and punish them according to the law," the police said in the statement.
Nobody died in the protests, the Yuhang government said on its website.
Similar protests have also succeeded in getting projects shut down elsewhere in China.
The eastern city of Ningbo suspended a petrochemical project after days of demonstrations in November 2012, and protests forced the suspension of a paraxylene plant in the northeastern city of Dalian the year before.
Hangzhou, capital of prosperous Zhejiang province and best known in China as the site of a famous lake, has seen its lustre dimmed in recent years by recurrent smog.
About 90,000 "mass incidents" - a euphemism for protests - occur each year in China, triggered by corruption, pollution, illegal land grabs and other grievances.
Late in March, hundreds of residents of the southern town of Maoming staged protests against plans to build a petrochemical plant for fear it would contribute to pollution.