Customs officers have seized 8,000 and 40,000 ecstasy tablets in Cork city.
The 'Eight' cigarettes - which had originated in China - were detected by revenue officials in Portlaoise Mail Centre, and a controlled delivery was carried out.
This led customs to a residential premises on Cork's southside where the cigarettes were recovered, along with 40,000 ecstasy tablets valued at around 400,000.
A cannabis grow house was also discovered during the operation.
Two Chinese nationals, a man and woman both in their early 30s were arrested and taken to Bridewell Garda Station for questioning.