“It is absolutely unacceptable that Chinese or foreign journalists should be banned from working in Guiyu, believed to be the world’s biggest toxic waste site,” said Reporters Without Borders.

“We strongly condemn the determination of some local owners, with the backing of the authorities, to prevent access to information by force, and the problems for the press in probing the hidden face of China’s economic miracle,” it said.

“We urge the authorities in Guangdong to ensure the press free access to Guiyu.”

French freelance journalist Michael Sztanke and two colleagues were surrounded by around 30 men just after they finished filming at Guiyu on 1st March 2006. They were forced to hand over some of their video tapes.

“We spent 45 minutes trying, unsuccessfully, to negotiate with them, Sztanke told Reporters Without Borders.”Then things got out of hand and they stole the tapes and told us not to come back to the region.”

A few days earlier, a Japanese television crew were set upon by several hundred owners and workers Guiyu. The Japanese journalists had both their tapes and video equipment seized.

Police did not intervene on either occasion.

Guiyu is a community of four villages on the banks of the Lianjiang river, some 200 kilometres north-east of Hong Kong. More than 100,000 people, who are paid the equivalent of around 1.50 euros a day, use their hands to strip down and sort electronic equipment, in defiance of the most elementary public health regulations.

“The working conditions on the sites are horrible. In Guiyu, in south-east China, I have seen vats of acid spilling into the rivers. They were so corrosive they could dissolve a coin in one hour,” said Kevin Bridgen, a scientist working for Greenpeace International.

“Many of the chemicals used in the electronic industry are dangerous and can be harmful to health even at very low concentrations,” he said.