Shops in the UK are being staffed with foreign nationals enslaved by organised crime gangs according to a new government report.

The Gangmasters & Labour Abuse Authority’s (GLAA) report explored the scale of worker exploitation. It claimed retail is one of the 10 most prevalent sectors where foreign nationals are recruited by organised crime groups who charge the staff for finding the work.

In one convenience store raided by immigration officers last year, a staff member without the right to work in the UK was paid 33% below minimum wage and worked 60-70 hours a week.

In another case, when police interviewed an illegal off-licence shop worker, the staff member claimed they received only transport costs and food instead of pay.

In a third newsagent brought before a licence review after several licence breaches, a councillor alleged that an illegal worker found in the store was likely paid below the minimum wage.

All three shops, which fell within three miles of each other, were prosecuted in the same year and all were also found to be selling illicit tobacco and/or alcohol.

Car washes were also listed by the new report as “one of the largest industries in which labour exploitation is said to occur”. The Petrol Retailers Association claimed there are 20,000 unregistered hand car washes in the UK. The organisation’s chairman Brian Madderson said: “These car washes are often controlled by gangmasters, in many cases employing modern slaves.”

One car wash worker at a petrol garage in London told Retail Express that he had no paperwork allowing him to remain in the UK and that this was used to withhold pay and prevent staff from complaining.

Since gaining police powers last May, the GLAA has arrested 107 people, identified 1,335 abused workers and launched 181 investigations. The GLAA’s head of operations Ian Waterfield said: “There is much more to do. Slavery and exploitation continues to thrive in every town and every city and our dedicated workforce will continue to build on what we’ve achieved.”

The National Crime Agency believes there are “tens of thousands” of slaves in the UK.

Read more: Convenience sector shamed over repeated minimum wage failures