Two people were arrested following a multi-agency operation in the Buncrana district earlier this week.
A number of searches were carried out in the area on Monday as part of the operation which involved Gardaí, immigration officers, the Department of Social Protection and Revenue & Customs.
As a result, two people were arrested and detained while three vehicles were seized also.
Gardaí said that a “number of offences” were detected, and that operations similar to this would take place over the Christmas period.