Gardai in Letterkenny yesterday carried out a major operation in a clampdown on the illegal sale and supply of drugs in the town.
Officers raided a number of houses in the town and arrested a total of five people.
The five include three men and two women believed to be involved in the drugs trade in the town.
A quantity of drugs was also seized during the raids.
All five suspects were taken to local Garda stations where they have remained for questioning overnight.
The five are due to appear at Letterkenny District Court later this morning.