Revenue officers have seized 65,000 unstamped cigarettes and more than €1,500 in cash in Cork.
Officers made the discovery when they carried out a search, under warrant, of a residential property in the city.
The cigarettes, branded Minks, Marlboro and NZ, were discovered with the assistance of detector dog Eva.
They had a combined retail value of more than €39,000, representing a loss to the Exchequer of about €31,000.
A total of €1,530 in cash was also seized as officers suspected it to be the proceeds of, or intended for use in criminal activity.
A man in his 30s was questioned in connection with the seizure.
At Cork District Court on Friday, Judge Patricia Harney granted Revenue officers a three-month cash detention order to allow for further investigations to be carried out.