Ecstasy and ketamine worth an estimated €108,000 have been seized at a premises in Athlone.
The drugs, which had originated in the Netherlands and were destined for addresses in Dublin and Waterford, were discovered in parcels on Tuesday.
Separately, Revenue officers examining parcels at a premises in Dublin last week seized drugs and prescription medicines with an estimated value of €206,000.
They originated in the USA, Canada, Spain, India, and the UK and were destined for addresses nationwide.
Two imitation firearms were also seized and investigations are ongoing.