Drugs worth more than €225,000 were seized by Revenue on Monday as a result of routine operations in the Athlone and Dublin mail centres.
The illegal drugs weighed a total of more than 99kg and included herbal cannabis, khat and cocaine.
They were found in more than 50 separate parcels, which originated from the UK, the US, Canada, Kenya, and Spain. The parcels had been declared as items including fishing bait, keychains, art supplies, green tea and sports shoes, and were destined for delivery to various addresses across the country.
The seizures were made with the assistance of two Revenue detector dogs, both named Bailey, who each operated in one of the mail centres.
Investigations are ongoing following the seizures.
Anyone with any information regarding smuggling is asked to contact Revenue on the confidential phone line 1800-295295.