A new task force to tackle tax dodgers in Devon and Cornwall's grocery and retail trade has been launched by HM Revenue and Customs.
The specialist team is targeting the sector in the South West and, along with similar operations in South Wales, North Wales and the North West, is expected to recover more than £7 million for Treasury coffers.
David Gauke, the Exchequer secretary, said: "We have made it clear that we will not tolerate tax evasion and we are determined to crack down on the minority who choose to break the rules.
"Everyone needs to pay the taxes they owe in full. It is not fair that at a time when most hard-working people are paying the right tax, others are trying to get out of paying what they should."
They bring together various compliance and enforcement teams for intensive bursts of activity targeted at specific sectors and locations where there is evidence of high risk of tax evasion.
The teams will visit traders to examine their records and carry out other investigations. They typically focus on groups of up to around 300 customers. The first task force targeted the restaurant trade from May last year.
Mike Eland, director general for enforcement and compliance at HM Revenue and Customs (HMRC), said: "These task forces bring together specialists from across HMRC to find people who are not paying what they should.
"If people have paid all their taxes they have nothing to worry about. But for those deliberately evading tax, be warned that HMRC is coming after you. We are on target to collect more than £50 million as a result of task forces launched in 2011-12."
Anyone aware of someone evading their taxes can contact HMRC via the tax evasion hotline on 0800 788887, email or by post. Full details can be found at www.hmrc.gov.uk