The CAB, backed up by the armed Regional Support Unit and local officers, swooped on four properties in the Mid-West: two in Limerick City and one in both Clare and Tipperary.
Properties searched included a dwelling in a halting site in Limerick City – the home of a couple, aged in their late 30s/early 40s.
In addition, CAB raided two professional offices, one in Limerick and the other in Tipperary, as well as a motor dealership in Clare.
Sources said the gang leadership is related to a major drug trafficking organisation, based in another halting site in Limerick City, which is involved in the supply of drugs in Munster.
The gang is also believed to be connected with another significant Traveller gang and, in addition, is associated with the Limerick-based Keane-Collopy criminal network.
Sources said the outfit hit in yesterday’s operation was targeted in relation to the “suspected purchase of land”.
The purpose of the investigation is to establish whether or not the lands were bought through criminal proceeds.
If this can be established it will allow CAB to initiate seizure proceedings, which would be progressed through the courts.
An amount of documentation, including mobile phones, devices and computer equipment, have been removed from the properties searched.
Teams at CAB headquarters in Dublin will sift through and examine the documentation to see if they can establish the source of money used.
The operation targeting this gang began earlier this year and yesterday’s move marked a “significant development” in the investigation, sources said.
The armed RSU took part in order to provide a high-visibility presence and did not reflect that any resistance was expected, of which there was none in the searches, sources said.
Gardaí said there were no arrests planned during this phase of the investigation.