Documents, phones and other electronic devices have been seized in a series of CAB raids.
Two homes in Dublin 6 and 15 were searched early today.
Two professional premises - one in Dublin 2 and the other in Laois - were targeted.
The Guards say about €40 grand's been frozen in an account in a financial institution in line with the money laundering laws.
Officers say its a significant development in an on-going operation targeting an organised crime gang involved in the cultivation, sale and supply of controlled drugs.
CAB's also investigating the beneficial ownership of a home in South Tipperary and another home in North Cork.