Almost €4m worth of cocaine and cannabis has been seized in four separate operations in Dublin and Limerick.
The most significant haul came after gardaí searched two cars in a car park at Liffey Valley at around 7:10pm yesterday.
Investigators found what they believe to be cocaine worth around €2.8m during the searches.
Three men and one woman, all aged in their 40s, were arrested on suspicion of drug trafficking offences.
They are being held at Clondalkin, Ballyfermot and Lucan Garda stations.
Gardaí also found €50,000 in cash during a follow-up search at a house in County Meath.
It is reported the drugs were being moved from a car with a Dutch registration plate to an Irish registered vehicle.
Separately gardaí found cannabis herb worth around €800,000 after stopping and searching a car in Rathcoole at around 6:30pm yesterday.
A man in his 40s was arrested.
He is being held at Clondalkin Garda Station.
Meanwhile, a man was arrested after Gardaí uncovered €200,000 worth of cannabis in a pre-planned raid in Finglas in North Dublin.
Finally, a man in his late 20s was arrested in Limerick after cocaine worth €70,000 and €10,000 in cash was discovered at a house in the Castleconnell area.