The slave master responsible for the kidnapping and imprisonment of hundreds of children and impoverished workers in brick kilns has been sentenced to death.

Zhao Yanbing, a brickyard employee, was convicted of murder after admitting on national television that he battered a man to death with a shovel. “His performance was bad so I thought I would frighten him a bit,” said Zhao. “When I raised the shovel over him I never thought that he would confront me, so I slammed the shovel down on his head.”

The victim, identified as a mentally handicapped man named Liu Bao, never got up again.

A further 28 people were given prison sentences, ranging from two years to life, after being convicted of forced labour, illegal detention and causing injury at the brickworks in northern Shanxi province.

The jail terms are the first to be handed down in a scandal that has shocked the nation and raised questions about how officials could have turned a blind eye to the abuses.

Delivering his ruling, Liu Jimin, a judge with the Shanxi High Court, said: “These cases have had a vile effect both domestically and overseas and can only be handled . . . in the most severe fashion.”

Heng Tinghan, the foreman at the brickyard, was given a life sentence on charges of intentional injury and unlawful detention. The owner, Wang Bingbing, was jailed for nine years. The brickworks was in a courtyard belonging to Wang’s father, a local Communist Party chief, who has since been expelled from the party.

The scandal surfaced last month after about 400 distraught parents posted a plea on the internet to the Government to help them to find their missing children. They feared that the children, mostly teenage boys, had been sold into slavery in Shanxi province and neighbouring Henan. Officials say that 576 enslaved workers have since been rescued, but the true number is believed to be far higher.

Heng, 42, lured 32 rural labourers with job offers, then forced them to work in the brickyard. They ranged in age from 14 to 58 and included seven who were mentally handicapped.

He had become the chief villain in the scandal after state media said that a worker died at the kiln he ran in Hongtong county’s Caosheng village, and broadcast pictures of workers with their skin rubbed raw or severely burnt. Across the region workers as young as 8 were recruited from bus and train stations with false promises, or abducted off the street and then sold to kilns for 500 yuan (£35) each.

Chinese leaders have made improving the plight of millions of migrant workers a priority, yet exploitation, non-payment of wages and other abuses remain common.

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