The men, aged 44, 31, and 28, were arrested last Thursday (January 21), with two women also interviewed in relation to allegations of money laundering.
The arrests came as Northamptonshire County Council trading standards, in conjunction with Northamptonshire Police and supported by the East Midlands Government Agency Intelligence Network, investigated a series of rogue trading offences between April 2013 and November 2015 across Northamptonshire, Lincolnshire, Leicestershire, Bedfordshire, Cambridgeshire and Norfolk.
Warrants were executed at three locations in Northamptonshire, with additional support from the East Midlands Operational Support Service (EMOpSS) and the National Crime Agency.
Officers from Her Majesty’s Revenue and Customs and Department of Work and Pensions were also in attendance.
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An emaciated dog was also recovered from one of the premises, which was seized by the RSPCA. Inspectors will interview the owner in relation to neglect.
The three men and one of the women, from Raunds, were bailed pending further inquiries.
Cllr André González de Savage, the county council’s cabinet member for strategic infrastructure, economic growth and public protection, said: “This joint operation is a great example of how agencies can work together to put a stop to rogue trading.
“These types of cold callers usually target the most vulnerable members of the community, particularly the elderly, and take advantage of their often trusting nature.
“If you’re concerned about a caller at your door or suspect rogue traders are operating in your community, contact the Doorstep crime Action Network on 0345 23 07 702 or the Citizens Advice Consumer Service on 03454 04 05 06.
“If a crime is in progress, dial 999.”