Italian customs and financial police have raided what authorities call the country’s largest illegal cigarette production site to date, seizing over 150 tons of counterfeit cigarettes from an underground factory hidden near Cassino, southeast of Rome.

The clandestine facility spanned some 1,600 square meters and operated behind a sophisticated concealment system. Investigators discovered a hydraulic mechanism hidden within a logistics warehouse that allowed access to the subterranean production area.

Inside the bunker, officers found three fully operational processing and packaging lines, an air-ventilation system to suppress detectable exhaust, and living quarters for staff.

Authorities estimate the factory pumped out over seven million counterfeit cigarettes per day — roughly 2.7 billion units annually.

The operation’s scale allowed for significant illegal profit. Officials say the facility generated annual revenues of around €900 million, and they have already flagged €600 million in evaded taxes.

To date, one person has been arrested and multiple suspects identified.