A senior official from the Guangdong provincial capital said poor social management was one of the major reasons behind the unrest in Zengcheng, a suburb of Guangzhou, early this month. Zhang Guangning, Party chief of Guangzhou city, made the remark on Wednesday after he held talks with migrant workers, neighborhood management personnel, company managers and villagers in Dadun village where the clash happened.

"The causes of the clash are complicated, but our social management has lagged behind economic growth, and it was one of the major reasons that led to the clash," he said.

He urged relevant departments to learn from the case, improve social management and provide better service to the city's migrant workers who have played a big part in Guangzhou's economic development.

"Relevant departments should do what they can to help increase the migrant workers' feelings of belonging and sense of happiness in Guangzhou," Zhang said.

"Guangzhou, which has millions of migrant workers from around the country, is a city that has a high tolerance to outsiders," he added.

Zhang promised to seriously punish those who broke laws and regulations in the clash.

The unrest erupted on June 10 after a pregnant woman in Dadun village got into a dispute with local security personnel who asked her to move her stall, which was placed in front of a supermarket.

Later in the night more than 100 people gathered in front of the supermarket, some of whom hurled bottles and bricks at government officials and police vehicles. They later marched toward the nearby Dadun public security station, damaging several police vehicles and private cars with rocks.

On June 11 and 12, people again gathered around the public security station, vandalizing vehicles and automatic teller machines and attacking police officers.

The unrest was brought under control and order was restored on the morning of June 13, according to local authorities.

Police later arrested 19 suspects on charges of obstruction of official affairs, causing a disturbance and intentional damage of property, according to a statement issued by the Zengcheng government on June 16.

Three police cars, an ambulance, a bank ATM, plus many local private cars were damaged, but no deaths were reported.

However, the case has raised great concerns at home and abroad.

Yin Shengyong, a Guangzhou white-collar worker, said government departments have to expand contact with residents and make their work more transparent to avoid similar cases happening again.

"Now government departments and local residents, particularly migrant workers, lack mutual trust," he said.

Wang Fuqing, a migrant worker from the Guangxi Zhuang autonomous region, said clashes between migrant workers and government personnel usually happen when the migrant workers' legal benefits are damaged.

"Migrant workers are a disadvantaged group and they often receive unfair treatment," she added.