None were prepared to discuss their supply chains.

“They’re illegal … I don’t know where we get them, I’m not the manager,” one seller told this masthead.

Almost all stores sold Manchester cigarettes, and many also stocked Chinese brand “Double Happiness”, Korean brand “ESSE”, imported “Marlboro Reds” and “Winfield Blues” among others.

Prices ranged from $17 to $25 a pack – about 50 per cent cheaper than most legitimately taxed plain-packaging equivalents.

More than 5.2 million cigarettes and 1.2 tonnes of loose tobacco were seized from Queensland retailers in a 12-week blitz from July.

About 8500 illegal vapes and 12,000 nicotine pouches were also found.

Organised crime is believed to control about 75 per cent of the market.

Brisbane Times has been told at least 350 retail businesses across Queensland are under investigation by Queensland Health, which is responsible for enforcing tobacco regulations.

About 440 petrol stations, convenience stores, gift shops and tobacconists were targeted during the three-month crackdown from July this year.

At least 13 businesses are being prosecuted in court.