The country's top trade union body yesterday ordered a nationwide campaign on labor use as police arrested more suspects accused of using forced laborers in brick kilns.

The All-China Federation of Trade Unions said it requires grassroot trade unions across the country to immediately carry out a thorough examination to stop the violation of migrant workers' rights.

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It instructed trade unions at all levels to unearth the hidden problems and cooperate with the government in cracking down on offenders.

"The All-China Federation of Trade Unions was extremely shocked and indignant on hearing of the slave worker case," Zhang Mingqi, a senior official with the federation, said.

"We can never tolerate such a thing happening in our socialist country."

The announcement of the campaign follows media reports of hundreds of slave laborers being used in small brick klins and mines in Shanxi and Henan provinces.

Five suspects have been arrested for illegally holding and deliberately injuring laborers in a North China brick kiln and forcing them to do highly intensive manual labor, the Xinhua News Agency reported yesterday.

They are kiln boss Wang Bingbing, foreman Heng Tinghan, and hatchet men Zhao Yanbing, Heng Mingyang and Liu Dongsheng. The five have confessed to the charges, local police said.

Some of the slave laborers freed by police from a brick kiln in Shanxi's Hongtong county. [China Daily]

Police are searching for a further three suspects, namely Zhou Xueping, Chen Zhiming and Jin Xingjian.

Zhang said the campaign would target industries that employ large numbers of migrant workers, such as manufacturing, construction, mining and restaurants.

He admitted the trade unions had failed to play a significant enough role in rural areas, which have produced more than 200 million migrant workers.

"Although cases of slavery like the one at the brick kiln in Hongtong county are extremely rare, we have found from our investigations that migrant workers in most small brick kilns, coal mines and smelteries have to endure poor and even harsh conditions regarding pay, safety and hygiene," Zhang said.

"There is still a long way to go to protect workers' rights."

He said the federation would strengthen its work in rural areas in the future to keep pace with the rapid urbanization.

The federation said it wanted to recruit more than 10 million rural migrant workers as trade union members this year.

At the end of last year, 41 million migrant workers had joined a trade union.

The International Labor Organization in Beijing said it welcomed the government's condemnation of illegal and dangerous workplaces and encourages further investigation, rescue and fair compensation.