Gardaí arrested 31 people in the Waterford Area over the past two days as part of a crackdown on serious crime.
Searches, checkpoints, arrests and warrant executions were carried out throughout the city as part of Operation Storm.
One person was arrested in connection with the sale and supply of drugs, while six were arrested for drug possession.
Seven premises were searched and three vehicles were seized.
Other people were arrested for crimes including assaults, robbery and burglaries.
Sixteeen suspects have been charged and will appear at local sittings of Waterford District Court in the coming weeks.