As many as 10,000 people could be working in slave-like conditions in textile factories in Leicester.
Leicestershire MP Andrew Bridgen has told Sky News a "conspiracy of silence" has allowed factories in the city to continue to exploit workers over many years.
"You've got a systemic failure of all the protections in Leicester that would prevent this from happening," Mr Bridgen said.
"I've estimated it's around 10,000 individuals who are effectively in modern slavery providing garments for internet retailers."
The claim comes on the same day a report based on police records found that across Britain there are at least 100,000 slaves.
The study by the Centre for Social Justice think-tank and the anti-slavery charity Justice and Care claims the issue is likely to intensify in the wake of the coronavirus pandemic.
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Leicester City Council estimates there are around 1,500 textile factories across the city.
Most are small businesses – workshops housed in crumbling buildings that are in desperate need of repair.
Smashed windows are patched up with cardboard. Fabric is draped so it's impossible to see inside.
For decades there have been claims some factories pay workers well below £8.72 per hour, the national minimum wage.
The government's Health and Safety Executive is investigating allegations some factories forced people to work in unsafe conditions during lockdown.
"The internet retailers have flourished during the COVID crisis because their competition has been shut down. So we've seen a huge extra demand for the products," said Mr Bridgen.
Many of the factories lie within the Leicester East constituency of MP Claudia Webbe.
She says she has been contacted by anonymous workers who are too scared to speak out publicly because many are in the country illegally.
"Machinists are being paid £3 an hour, packers are being paid £2 an hour. That is what seems to be the standard," she said.
Outside one factory a worker who asked not to be named told Sky News she is paid between £5 and £6 an hour.
"Very little money" she said, in broken English.
Immigration officers patrol the streets outside the factories and a multi-agency investigation is under way.
Many feel it is long overdue.
When asked if claims of widespread exploitation in the city are an "open secret", deputy mayor Adam Clarke replied: "You call it an open secret. It's just open.
"There are doubtless workplaces in the city that are unsuitable.
"We've been aware of this for a very long time and have been working with enforcement agencies to try to ensure that there is effective regulation enforcement.
"The network of agencies that have responsibilities is just too complex.
"There are just too many organisations, HMRC [HM Revenue & Customs], the GLAA [Gangmasters and Labour Abuse Authority], the HSE [Health and Safety Executive] and others have enforcement responsibilities. There needs to be one enforcement body and that needs to be set up as quickly as possible.
"This is a systemic issue that is borne out of poor regulation, poor legislation and exploitation at every level.
"You have to ask yourself who actually has the power to change this? And that buck stops with government."
A Home Office spokesperson said: "We take all allegations of modern slavery extremely seriously and are determined to ensure ruthless criminals who exploit vulnerable people face the full force of the law.
"The National Crime Agency and others are looking into the appalling allegations about sweatshops in Leicester and the home secretary has been clear that anyone profiting from slave labour will have noRead More – Source