The western province of Izmir hosts the factories of Turkey’s biggest cigarette makers. On Tuesday, some 40 kilometers (some 25 miles) away from them, police discovered the country’s biggest illegal cigarette factory in Kemalpaşa district.

The factory was not much different from its licensed, legal peers, with fully automated machines churning out tobacco products and packaging them. Authorities detained 18 suspects and seized more than 10 million cigarettes as well as 5.5 tons of tobacco ready to be converted into cigarette rolls.

The site was discovered after an operation by police anti-smuggling units. Cigarettes, machines and other materials related to tobacco production were seized inside the 2,000-square-meter (21,527.82-square-foot) factory, in a warehouse in Buca district and inside a truck in Torbalı district, all linked to the suspects.

Security sources quoted by Turkish media said it was the biggest seizure of cigarettes in a single operation ever. The estimated value of the seized materials and cigarettes were around $3.7 million (TL 50 million).

Counterfeit and smuggled cigarettes make up a lucrative sector in Turkey where the prices of tobacco products have skyrocketed in recent years, just like the prices of alcoholic beverages which are subject to heavy taxes that drove some to purchase cheaper but deadly drinks. Security forces routinely launch raids against illegal sellers, who often sell cigarettes secretly in shops selling raw tobacco and hookahs.