Two men are still being questioned in Dublin garda stations following a series of raids by the Criminal Assets Bureau.
The bureau is investigating the activities of a north Dublin criminal gang involved in guns and drug crime.
Three business premises in Cavan, Meath and Dublin, including a solicitor's office, an accountant's office and a restaurant, have been searched.
The two men were arrested on suspicion of money laundering the proceeds of drug trafficking.
They are being held at Kevin Street and Crumlin Garda Stations.
