Revenue officers, along with the assistance of detector dog Robbie, discovered 25kgs of herbal cannabis in Dublin Port yesterday.
Officers seized the drugs which have an estimated street value of €500,000 during routine operations.
A shipment which had arrived from Almeria, Spain was stopped and searched.
In a separate incident at Portlaoise Mail Centre yesterday, 3.4kgs of herbal cannabis was seized.
As a result of routine profiling the drugs were discovered concealed in two separate parcels labelled as 'yoga cushions' and 'herbal tea'.
The drugs with an estimated street value of €68,000 were destined for addresses in Dublin and Tipperary.
Investigation s are ongoing with a view to prosecution.
Last week in a series of operations in Dublin Airport, Revenue officers made a number of seizures including:
2kgs of herbal cannabis seized from a 38-year-old Polish man travelling from Dubai. The drugs had an estimated street value of €40,000. The man was arrested by Gardaí and brought before the District Court where he was remanded in custody until July 3 for sentencing.
20kgs of tobacco and 7,000 cigarettes seized from two female Irish passengers travelling from Lanzarote. The tobacco branded "Amber Leaf" and cigarettes branded "Benson & Hedges" had an estimated retail value of €14,800 and represent a loss to the Exchequer of over €12,800.
Cash amounting to €15,571 (consisting of Euro, Sterling and US Dollar) believed to be from the proceeds of crime, seized by Revenue officers from three male passengers travelling to New York. A three-month cash detention order has been granted to Revenue officers to allow further investigations to be carried out.