GARDAI investigating the discovery of cannabis with an estimated street value of €2.5m have made two further arrests.
The detention of two men in their 30s came after two men - one aged in his mid-40s, the other in his early 50s - were arrested during the initial stages of the operation in Tuam, Co Galway, yesterday.
Around 3,000 cannabis plants were found in a business premises in the town.
The operation in the west of the country follows a raid in Co Meath on Friday night when 1.5 million euro worth of cannabis was seized in a separate investigation.
The plants and herb were discovered by gardai at a business premises in Kells.
A 53-year-old man and 43-year-old woman were detained during that raid.
Gardai described the find in Tuam as a "sophisticated cannabis growing operation".
In Kells, officers said a large cannabis cultivation operation was discovered.