Two men are due in court this morning in relation to the discovery of a "substantial" grow house in Co Waterford.
The Vietnamese men, aged 32 and 43, were arrested after 1644 cannabis plants with an estimated street value of more than €1.3m were seized.
As part of an intelligence-led operation, Gardaí from Tramore Drugs Unit, assisted by the Armed Support Unit in Waterford, searched an industrial premises in the Waterford Airport Business Park on Thursday at 6pm.
Initial estimates put the seizure at €800,000 but this was amended following a full examination of the site.
The men were detained at Tramore Garda Station under Section 2 of the Criminal Justice (Drugs Trafficking) Act, 1996.
They are expected to appear before a sitting of Waterford District Court at 9.30am this morning.