The arrests on Friday were seen as "a significant development"
Two men have appeared in court in connection with the use of ATM skimming devices.
The men, both aged in their 30s, were detained at Kildare and Newbridge Garda Stations after being arrested in the Blanchardstown area of Dublin on Friday morning.
They have appeared before the Criminal Courts of Justice charged in connection with the investigation.
They were arrested as part of an investigation into with the use of a skimming device on a bank ATM in Kildare town.
Gardaí, supported by the Garda National Economic Crime Bureau, had been working closely with a major bank in an attempt to catch those involved.
It is thought these criminals form part of an Eastern European criminal organisation.
The arrests were seen as "a significant development" in the case, which involved the targeting of eight different bank branches in Dublin, Kildare and Meath.
Detective Chief Superintendent Patrick Lordan of Garda National Economic Crime Bureau said: "Gardaí are working on a daily basis with the financial institutions to prevent fraud.
"I would again like to stress the importance of being vigilant in all your financial dealings.
"Pay particular attention to suspicious activity or unusual items in the vicinity of ATMs."