Gardaí are questioning four men following separate incidents in Dublin in which drugs valued at €600,000 were seized.
The drugs, which included ecstacy tablets and heroin, were recovered in three raids in Dublin.
The first find was made in Ballymun, when gardaí carried out a search on a house in the Poppintree area at 11pm.
Three men were detained after gardaí uncovered what is believed to be 50,000 ecstacy tablets, with a potential street value of €500,000, during the search.
The three men, two in their early twenties and one juvenile, were arrested at the scene and are being detained at Blanchardstown and Finglas garda stations under Section 2 of the Criminal Justice (Drug Trafficking) Act. They can be detained for up to seven days.
In a separate incident, gardaí seized what is believed to be heroin during a search on a car in Neilstown last night. A follow-up search on a house in the area revealed a further quantity of the drug.
In total, heroin with an estimated street value of €100,000 was recovered.
A male juvenile was arrested at the scene and is currently being detained at Ronanstown Garda Station under Section 4 of the Criminal Justice Act 1984. He can be held for up to 24 hours.