A woman in Belfast is the third shopper to find what appears to be an SOS message in at item of Primark clothing.
The handwritten note, which claims to be from a prisoner in China working under slave labour conditions, was reportedly found inside a pair of trousers bought by Karen Wisínska in a Primark store in Belfast in June 2011.
Ms Wisínska said the trousers had remained unworn and in a cupboard until she discovered the message in them earlier this week and contacted Amnesty International.
The message, headed "SOS! SOS! SOS!" reads: "We are prisoners in the Xiang Nan Prison of the Hubei Province in China. Our job inside the prison is to produce fashion clothes for export.
"We work 15 hours per day and the food we eat wouldn't even be given to dogs or pigs. We work as hard as oxen in the field.
"We call on the international community to condemn the Chinese government for the violation of our human rights!"
Primark is to open stores in the United States for the first time as it looks to replicate the success behind a 26 percent jump in profits in the last six months.
The retail chain, which has 269 stores across Europe, expects its first US shop will begin trading in Boston, Massachusetts, towards the end of next year.
The US has been a notoriously tricky market for UK retailers to crack, with Tesco and Marks & Spencer among those to experience failure.
Primark's new store in Boston will be in the Burnham Building in the heart of the city.
High-street clothing retailer Primark has announced a 26 percent rise in its operating profit to £298 million for the past six months.
The company has also made its first "long-term payment" to victims of the Rana Plaza clothing factory disaster in Bangladesh, owner Associated British Foods said in its half yearly report.
ABF urged other retailers who source clothes from Rana Plaza to donate to a trust fund "so that it can pay out in full to the remaining victims".
Tomorrow will be the first anniversary of the disaster, in which more than a thousand people were killed.
Primark hailed its "outstanding year" today after revealing annual profits had jumped by 44% to £514 million - contrasting the fortunes of high street rival Marks and Spencer.
The retailer grew sales by 22% to £4.3 billion in the year to September 30 and the Associated British Foods, which owns Primark as well as leading food brands Twinings and Kingsmill, said it expected another improvement in performance in the current financial year.
The company paid tribute to Primark's buying teams after autumn/winter and spring/summer ranges sold out with little discount, while M&S struggled to kickstart its clothing sales.
Primark has expanded in the UK's major cities with the opening of a second store on London's Oxford Street and extensions to shops in Newcastle and Manchester.
They are also set to open their first store in France, which will be located in Marseille.
New UK support of £4.8 million will go towards the International Labour Organisation's ‘Improving the Working Conditions in the Ready Made Garment sector in Bangladesh’ programme to improve fire safety and protect workers.
International Development Secretary Justine Greening said:
“April’s factory collapse took a dreadful toll on people in Bangladesh and galvanised much-needed action on safety. Six months on, this UK action will help the Government of Bangladesh, employers and manufacturers make improvements on safety and conditions.
“But there is still a long way to go. Everyone needs to continue to work together to maintain momentum and prevent future tragedies.”
Primark has shown ITV News details of its strategy to track down the 550 workers who were employed by its subcontractor in the Rana Plaza factory in Bangladesh.
The challenge is made harder by the fact that many of the workers and their dependants have left Dhaka and are spread the "length and breadth of Bangladesh," senior executive Paul Lister said.
Primark, working with the University of Dhaka, has devised a scheme whereby students will travel out to each of the victims in order to assess their level of need.
This data will be entered into touch tablets, which contain software to calculate the level of compensation they can expect.
High-end retailers are sourcing garments from the same factories in Bangladesh as Primark but are charging a higher price, one of the company's senior executives, told ITV News.
Paul Lister said: "If you look at who is sourcing out of Bangladesh, you'll see that clearly Primark sources out of Bangladesh, but actually next door to Primark in any given factory could be a Bond Street retailer, sourcing exactly the same sort of garment, sourcing a T-shirt.
"So ours at Primark would be £5 on our shelf, it could be £60 for the Bond Street retailer, in the same factory, with the same conditions, the same workforce, the same pay, as the £5 Primark T-shirt."
Senior Primark executive Paul Lister has told Business Editor Laura Kuenssberg that the company regularly makes unannounced checks on the 88 factories it uses in Bangladesh in a bid to improve safety standards.
A senior Primark executive, Paul Lister, has told ITV News that it was time for their "competitors to step up to the plate" and compensate victims of the Rana Plaza disaster in Bangladesh