A surprise operation to tackle suspected security licence fraud, labour exploitation, and immigration offences was launched in Berkshire.
The Security Industry Authority (SIA) targeted Reading as part of their nationwide crackdown on October 31.
The operation was one of several synchronised, unannounced visits with Home Office Immigration Enforcement.
Targeting 11 locations across England, it was aimed at disrupting potential organised criminal activity linked to security company staff working at construction sites throughout the country.
Two people were arrested in Yeovil and Ilkeston for overstaying their visas.
An individual in Ilkeston was also cautioned under section 22 of the Private Security Industry Act.
The extensive enforcement and intelligence-gathering operation was initiated after the SIA’s Intelligence Team received allegations of serious criminal activity, including SIA licence fraud, organised immigration crime, labour exploitation, and money laundering.
Pete Easterbrook, head of criminal enforcement at the SIA, said: "This operation was a result of intelligence originating from within the private security industry which was developed and analysed by our intelligence team and involved collaboration by our criminal enforcement and compliance and inspections teams.
"Thanks to these combined efforts, we have struck a significant blow against those seeking to use the private security industry as a vehicle for criminality, including the exploitation of vulnerable people.
"Operations like this are vital in our mission to protect the public by ensuring that those who seek to seriously undermine the regulatory regime are brought to justice."
The investigators targeted locations in Yorkshire, Somerset, Norfolk, Derbyshire, Staffordshire, East and West Sussex, Berkshire, and Lancashire.
Eddy Montgomery, director of enforcement, compliance, and crime at the Home Office, said: "Exploitation of illegal workers within the UK construction industry is on the rise, with rogue employers showing complete disregard to the safety and rights of legal foreign workers who contribute significantly to this sector.
"Our immigration enforcement officers are working closely with other government agencies to intensify efforts to tackle illegal working in construction as part of a broad series of operations across multiple sectors.
"I would like to thank the Security Industry Authority for their effective collaboration in cracking down on fraudulent employers who are violating laws, impacting public finances, and exploiting vulnerable people for financial gain."
The SIA is currently unable to provide further details of the arrests, given the potential impact on any future criminal prosecutions.
However, they have urged anyone who is concerned about labour exploitation within the private security industry to report it to them and other agencies.
Mr Easterbrook added: "Where we get credible intelligence of illegal activity, we have the will and capability to act decisively and take robust action."
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