More than 600 packets of contraband cigarettes have been confiscated from a stockroom of a shop in Ribbleton.
Trading Standards officers from Lancashire County Council inspected the premises along with Preston Police.
During the raid on Tuesday (26 March) officers also uncovered a suspected illegal immigrant.
The illicit tobacco was uncovered in the shop and in a vehicle parked nearby.
An assistant present in the shop was unable to produce any ID and claimed to be homeless.
Police arrested him on suspicion of being in the country illegally and he could face deportation.
Head of Lancashire County Council Trading Standards Paul Noone said: “The number of cases we are dealing with demonstrates the value of the illegal trade in tobacco, with some unscrupulous retailers clearly being reluctant to comply with the law on tobacco sales.
“The sale and manufacture of illegal tobacco has a serious impact on legitimate businesses, and our communities, and is something we’re determined to tackle.
“It has a negative impact on people’s health, with cheap illegal tobacco helping to keep smoking rates high, and being more affordable to children. Smoking remains the largest preventable cause of ill health and premature death in the UK.
“Our officers will continue to take robust enforcement action in relation to the sale of illegal tobacco in Lancashire, including seeking confiscation of any financial gain from offenders where possible.”
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Consumers can report sales of illicit tobacco to Trading Standards by calling the Citizens Advice Consumer Service on 03454040506.