CHAOZHOU, Guangdong - Nine people allegedly involved in a violent wage-related dispute have been detained, local police said on Tuesday.

More than 200 migrant workers, most from Southwest China's Sichuan province, gathered on Monday night in front of a government building in Guxiang township of Chaozhou, Guangdong province, protesting a wage-related dispute that has already led to the serious injury of a migrant worker.

The protest has drawn hundreds of people into escalating violence between migrant workers and local people.

At least three cars were smashed and another one burned in the violence, local police said, with dozens of people injured.

The crowd in front of the township government building was dispersed by police at about 10:30 pm, according to local police on Tuesday. Police did not disclose if there were any casualties in the incident.

The violence was reportedly caused by the serious injury of a migrant worker, surnamed Xiong, from Deyang city of Sichuan, who works for a local ceramics factory.

Xiong, 19, was seriously wounded in a knife attack after he argued with the factory boss for owed wages at the workshop on June 1.

Xiong's father suffered a head wound in the conflict.

The boss, surnamed Su, and other two local people allegedly involved in the knife attack, were detained by local police on Sunday.

"The Sichuan people were too angry. They have already pushed down the gate of the Guxiang government building on Sunday night," a local shop owner surnamed Huang told China Daily.

On Monday night, migrant workers gathered on the street and smashed cars and shops on the street, according to Huang.

After the incident, the Guangdong provincial public security department ordered local police authorities to carry out a full investigation into the case, calling for better protection of migrant workers' rights.

Deng Jianhua, deputy director of the information office of Sichuan's Deyang city, asked for an open and thorough investigation into the violence.

"We are doing what we can to protect the rights of migrant workers from Sichuan. Please be assured that we will try our best," he wrote on his micro blog on Tuesday.

"But authorities in Chaozhou should make public why workers from Sichuan were so angry and took such an extreme action to protect their rights," he added.

Chen Guang, a doctor with Southwest Jiaotong University, suggested local authorities respond promptly to migrant workers' demands for payments, given that China has reported a rising number of wage-rated disputes and violent cases in recent years.

"The authorities should fully study such disputes. Otherwise, they will easily escalate into social violence," Chen said on Tuesday.