The UK-based grocery-store chain Tesco has halted production at a factory in China after a report that the factory used forced labor to produce Christmas cards.

A Sunday Times report said a 6-year-old London girl found a disturbing handwritten note in a Christmas card purchased at the chain in which the author described being a foreign prisoner forced to work.

Similar pleas detailing forced labor in China have popped up in clothing and other products in the UK and the US.

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Tesco, the massive UK-based grocery-store chain, has announced that it halted production at a factory in China over a claim that the factory used forced labor to produce Christmas cards.

Peter Humphrey broke the story at The Sunday Times that a 6-year-old girl in South London found a handwritten plea for help inside a Christmas card she bought from Tesco.

The front of the card was decorated with a kitten in a Santa hat, but the inside contained a disturbing message from someone claiming to be a prisoner who was forced to work.

„We are foreign prisoners in Shanghai Qingpu prison China,“ the message said in capital letters. „Forced to work against our will. Please help us and notify human rights organization.“

The girl’s father, Ben Widdicombe, told the Associated Press that the family initially thought the note was a „prank.“ They soon realized it was legitimate, however, and contacted Humphrey, who was requested by name in the note. Humphrey as a corporate investigator was detained for several years in China in the same prison.

Tesco said in a statement after the report that all the cards had been pulled from sale, that it had suspended its use of the factory, and that because the grocery giant „would never allow“ the use of prison labor in its supply chain, it was launching an investigation.

„We have a comprehensive auditing system in place and this supplier was independently audited as recently as last month and no evidence was found to suggest they had broken our rule banning the use of prison labor,“ the statement said. „If a supplier breaches these rules, we will immediately and permanently delist them.“

Similar pleas from forced labor in Chinese facilities have surfaced in the West before.

Primark launched an investigation in 2014 after finding a note written in Chinese that was hidden in a pair of pants claiming inmates were forced to make clothes for 15 hours a day, the BBC reported.

In 2017, a Walmart customer found a note in a purse detailing harsh conditions that included 14-hour workdays, beatings, and malnourishment at a prison in the Chinese region of Guangxi.

China’s massive rise as an economic giant has capitalized on „the production of labor-intensive, cheap goods for export“ that has created instances of forcibly employing children, disabled people, and federally detained people in dangerous work conditions, according to the Global Slavery Index.