More than 1,000 children may have been kidnapped and sold into slave labour in a brutal human trafficking ring that has shocked and outraged China.

The children, some as young as 8, worked in brick kilns for 16 hours a day with meagre food rations. They were guarded by fierce dogs and thugs who beat their prisoners at will.

Many were abducted right off the streets of cities in the region and sold to factories and mines for as little as 400 yuan (£27). The unfolding scandal, involving negligent law enforcement and even collusion between government officials and slave masters, burst into the open this week.

Horrified Chinese have followed the stark, unusually frank images of the slaves on television as they were rescued by police. Some children still wore their school uniforms.

They lived in squalid conditions with many adult workers, sleeping on filthy quilts on layers of bricks inside the brickworks, with the doors sealed from the outside with padlocks and the windows barred with pieces of wood.

Many children had festering wounds on their black feet and around their waists, apparently from burns. Some were even beaten to death by their guards.

Some 35,000 police have raided 7,500 kilns in Henan and Shanxi provinces in central China and rescued 468 people. Local officials said that 250 people had been arrested. They said the number of children forced to work in the kilns could rise to more than 1,000.

The abuses came to light only after 400 parents of missing children posted a letter on the internet pleading for official attention to their plight.

Filmed by television reporters from Henan province who accompanied the parents into the kilns to try to find their missing sons, several boys stood dazed and almost mute.

Asked if he wanted to go home, one boy gripped his filthy shirt and sobbed: “I want to. I want to.”

Zhao Yanbing, a foreman who fled a brickworks where 31 men were rescued a few days ago, described on state television how he had beaten a man in his late fifties for not working hard enough. “His performance was so bad, so I thought that I would frighten him a bit. When I raised the shovel over him I never thought that he would get up and confront me, so I slammed the shovel down on his head.” The man never got up again.

The revelations have sparked nationwide disgust. The Polit-buro, the Communist Party’s top decision-making body, sent a team of officials to Shanxi yesterday to investigate.

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