Image caption Residents in Shifang city were protesting over environmental and health concerns

Chinese officials have halted the construction of a copper alloy plant in Sichuan province following violent protests by local residents.

Local officials said large crowds of residents gathered on Sunday and Monday in Shifang city to protest against the plant on environmental grounds.

Both police and residents were injured in the clashes as bottles were thrown and cars damaged, they said.

Officials said they would now consult residents on the project.

Local authorities said hundreds of residents and students were involved in the protests, while state-run Global Times, quoting an unnamed police officer, said "several thousand" took part.

A statement on the incident on the city's Sina Weibo account said the government would not restart the project "until the majority of people support it".

Analysis This is not the first time that protests over the environmental impact of heavy industry plants have broken out in China. In recent years, the public has become more aware of its rights - and more vocal when it comes to issues of public health. While China has achieved astonishing economic growth in the past few decades, it has come at a huge environmental cost. The country's growing middle class worry about air and water pollution. They are concerned about the impact it will have on their children and are increasingly prepared to protest. Last year, the authorities were forced to close a chemical plant in the north-eastern city of Dalian following similar protests. Authorities face a huge challenge - they must balance the demand for continued economic growth against rising public anger over pollution. Recent high-profile mass protests in China

"Work teams will be sent to all communities and schools to listen to people's opinions and suggestions," they added.

But one woman in Shifang told the BBC that the streets were still "completely chaotic", with the government sending out "lots of armed police and riot police". People were still gathered in front of the city government office, she added.

"The whole thing started with students. Shifang was to build something harmful for future generations, so the people felt very uncomfortable about it," she said.

Injured protesters

The Shifang city government said 13 protesters were injured and sent to hospital on Monday after police dispersed the crowd with tear gas.

"Some people gathered outside the government building and began to throw bricks and water bottles at the building, government workers and police officers from 13:30, resulting in some injuries to police officers," the city government said.

On Tuesday, Shifang police issued a warning to protesters.

"Anyone who has incited, planned or organised illegal gatherings, protest marches or demonstrations or those who have engaged in smashing and looting... will be punished severely," it said in a statement.

The statement also warned people against using the internet or text messages to organise "illegal gatherings".

Photos showing injured protesters were circulating online, but these could not be independently verified.