A driver has been arrested in Ballyshannon after testing positive for cannabis.
Gardai stopped the motorist yesterday and used the roadside drug testing device. Gardai say that further tests are awaited.
Another driver was arrested in Letterkenny last night after testing positive for cocaine.
It was also discovered that the motorist did not have a driving licence, insurance or tax.
Their van was seized and summonses and Fixed Charge Penalty Notices will follow.
Gardai have issued a warning drivers to never drive under the influence of either alcohol or drugs.