Garment workers in Myanmar who produce clothing for Primark were locked inside their factory by supervisors who tried to prevent them from joining anti-coup protests, testimonies given to the Guardian claim. Workers employed by GY Sen, which supplies Primark, claimed to the Guardian that their supervisors had sought to prevent them from missing work to take part in protests in the main city Yangon on 18 February. Up to 1,000 workers were trapped inside, according to workers, who said they were able to break free after several hours. According to workers, about 20 were subsequently fired for missing shifts to participate in the civil disobedience movement, through which vast numbers of people across the country have refused to work. The movement has paralysed the military junta, severely disrupting key sectors such as banking and trade. A spokesperson for GY Sen denied allegations that workers had been locked in or fired for protesting. Primark said it launched an investigation into the factory on 5 March after a local labour organisation raised concerns, but did not specify the details. It added that it would not place any further orders with the factory until the inquiry was completed. Garment workers, mostly young women, have played a leading role in demonstrations opposing the military, which ousted the country’s democratically elected government last month. Many are continuing to organise protests, despite the junta imposing a campaign of terror and intimidation against opponents. Union leaders protest in the day but spend their evenings in hiding, sleeping at a different location every night to avoid the security forces. After dark, police and soldiers go door-to-door, seeking out activists. On top of the dangers posed by the military, workers’ groups say many employees have also been threatened with dismissal if they miss work to protest. Primark said in a statement: “We will work with our supplier and, where required, other trusted third parties. If the factory is found to have breached our code [of conduct], we will work with the supplier and factory to remediate any issues.” It added that Primark had a longstanding and positive relationship with the supplier, saying: “We believe it is our responsibility to do all we can to support workers in our supply chain.” Workers at GY Sen said that, even before the coup, they were put under pressure to complete excessive workloads and threatened with dismissal if they refused extra shifts. Staff were paid as little as 1,200 kyat an hour (60p an hour) to work overtime, according to payslips seen by the Guardian. A spokesperson for GY Sen denied that the workers were not paid properly, saying: “We have paid them [for overtime] according to the standard rate under the law.” Garment workers interviewed by the Guardian said they would continue to demonstrate because they were determined not to live under a military dictatorship. One worker, who claimed to have been fired, said: “Under their rule, we have to fear everything.” Like many others, the garment worker had moved to Yangon for work, and said: “I no longer have a job and can no longer afford my rent. It’s not a good option to go home either. It’s so difficult.” Garment workers, many of whom are young people who feel their futures are at stake, were among the first to gather for large demonstrations in the wake of the coup. Workers’ recent experiences in forming unions and fighting for better conditions meant they were able to organise quickly, said Andrew Tillett-Saks, a union organiser who works with unions in Myanmar. Already, some have been forced to leave their homes, because they were not paid February wages and cannot afford rent, Tillett-Saks said. Myanmar’s multi billion pound-a-year garment sector employed about 700,000 workers before the pandemic and accounted for more than 30% of exports in 2019, according to the UN and EU. Western brands, drawn by the country’s cheap labour costs, have faced scrutiny over working conditions, however, and over the treatment of employees during the pandemic. Over the past year at least 10,000 Burmese workers were abruptly laid off. Companies now face a dilemma over whether to continue sourcing garments from the country under military rule, or end ties, cutting off a crucial source of employment. H&M has said it will pause new orders. The Industrial Workers’ Federation of Myanmar urged brands that have suppliers in Myanmar to publicly condemn the coup and to ensure that no workers should be punished for going on strike. A coalition of campaign groups, including Burma Campaign UK, Labour Behind the Label and No Sweat, has made similar calls. In response to the claims regarding the GY Sen factory, Primark said they were “very serious allegations” that, if true, would be in breach of the company’s code of conduct. “Our highest priority is to keep workers safe and well, and ensuring their rights and freedoms are respected,” the spokesperson said. “Given the current situation in Myanmar, we anticipate that conducting the investigation may be more challenging than usual.”