500k illegal cigarettes and tobacco seized across Wales
Almost two tonnes of illegal hand-rolled tobacco - enough to make two million cigarettes - was seized in Wales during the summer of 2015.
Nearly 500,000 illegal cigarettes were also confiscated during Operation Fetch.
The goods were found by tobacco detection dogs working with trading standards officers from across Wales.
Health Minister Mark Drakeford said the clampdown on illegal trading would help safeguard public health.
The Welsh Government said smoking was the biggest single case of early death in Wales, with almost 6,000 deaths annually, and the sale of illegal tobacco undermined work to reduce smoking rates.
It added it also compromised current tobacco control measures such as age-of-sale legislation, labelling and the ban on having tobacco on display in shops.
Mr Drakeford said: "I am very concerned about illegal tobacco because its affordability and availability threatens the health of children, making it so much easier for them to access tobacco. It also eliminates the price incentive for smokers to quit the habit.
"This is not a Robin Hood crime. It is criminality which deprives the public of vital revenue which is used to fund essential public and health services, including tackling the damaging impacts of tobacco itself but its effects extend far beyond that."
Matthew Cridland, chairman of the Wales heads of trading standards, said figures showed 15% of tobacco used in Wales was illegal - the equivalent of one million cigarettes being smoked a day.
"We want to work with all tobacco control partners to address not only supply but also demand for illegal tobacco and trading standards will continue to vigorously pursue all those who distribute and supply this product," he added.