Heroin with an estimated value of eight million euro has been seized after gardai searched a light aircraft.
Media reports suggest that the seizure took place at Weston Airport.
The drugs were recovered on Friday after the interception of the airplane and a vehicle in south county Dublin and Co Kildare, gardai said.
Two men in their 40s and 60s have been arrested on suspicion of organised crime activity.
They have been detained under the provisions of Section 50 of the Criminal Justice Act at a Kildare Garda station.
Assistant Commissioner Organised and Serious Crime, Justin Kelly, said non-commercial flights were being increasingly used to smuggle drugs.
“This is a hugely significant seizure of heroin, and the importance of disrupting criminal networks supplying this type of drug into our communities has been reinforced by the recent wave of overdoses in Dublin city centre.
“Worldwide, law enforcement agencies are seeing an increasing use of general aviation (non-commercial flights) to smuggle drugs.
“This operation shows the importance of multi-agency co-operation, in this case between An Garda Síochána, Irish Customs and the Maritime Analysis and Operations Centre in Lisbon, Portugal.
“I wish to commend the dedication and professionalism of all the personnel involved in this complex operation.”
Revenue and the Garda National Drugs and Organised Crime Bureau carried out the operation.
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