Police have arrested four people on charges of physically assaulting migrant workers at a hydropower construction site in Heyuan City, south China's Guangdong Province, according to the city government.

The migrants, principally hailing from Chongqing Municipality and Sichuan Province, were employed at the sit on the Dongjiang River near Heyuan City.

One of those arrested was named as Ye Dingfa, 36, head of the Fuyuan Hydropower Development Company's security team, who was detained along with three managers at the company's construction site.

The workers got involved into a heated disputed with Fuyuan Hydropower Development and contractor Qiutian Construction Engineering Company last Friday, after having gone unpaid for four months. The protest turned violent and eight workers are in hospital, with one in critical condition.?

A doctor with Heyuan People's Hospital said that worker Lei Mingzhong had suffered "brain death" and had virtually no chance of survival.

The local government has set up a mediation team with Fuyuan Hydropower Development Company having stated it would foot the bill for the workers' medical costs.

Meanwhile, work on the hydropower station has ceased until all disputes have been settled.

Finally, officials from Guangdong's department of construction arrived in Heyuan city to lead an investigation and to console the grieving families of the injured workers.

(Xinhua News Agency July 3, 2007)