Over €800,000 in cash was seized in a series of raids targeting a Coolock crime gang.
The cash was recovered at a house outside Bailieborough, Co Cavan, yesterday as part of an intelligence-driven operation.
It was one of five premises searched by officers from the National Drugs and Organised Crime Bureau during raids in Co Cavan and on the northside of Dublin.
The 38-year-old suspect, who was detained at the house where the cash haul was found, is originally from north Dublin.
The man has links to Coolock as well as Cavan and gardai are trying to establish who he was being used to launder money for.
One line of inquiry is that the seized cash could linked to the Kinahan cartel.
Several properties, including the man's Dublin home, were raided after the cash bust.
"He has connections in Cavan but this man is from Coolock and the obvious connection is to criminality out that way," a source told the Herald,
The suspect is said to have kept a low profile since moving to Co Cavan and had not come to the attention of local gardai.
Gardai said the search operation targeted members of an organised crime group suspected of being involved in large-scale trafficking of drugs and money laundering.
The 38-year-old was being held last night at Navan Garda Station.
"Yesterday we entered one premises in Co Cavan and commenced a search and later we entered another four premises," said Assistant Garda Commissioner John O'Driscoll, who is in charge of Special Crime Operations.
"The searches continued late into last night and into the morning.
"Following initial small sums of cash, other bundles of cash were found and the counting continues but is now at €800,000 and one male is in custody in Co Meath.
"This operation demonstrates the continued determination of An Garda Siochana to target organised crime through stopping the flow of money suspected to be the proceeds of crime and which provides the motivation for organised crime groups to trade in drugs".