Revenue officers seized around 1.5kgs of herbal cannabis in the Portlaoise Mail Centre yesterday.
The drugs, said to be worth around €30,000, were hidden in a parcel labelled as ‘clothing'.
The package came from the US and was destined for an address in Cork.
A 19-year-old Irish man was arrested by Gardaí and was detained under Section 2 of the Criminal Justice (Drug Trafficking) Act, 1996.