Far North mayor John Carter says road sign vandals are costing the council $100,000 a year and putting lives at risk.
In the latest incident, four traffic warning signs near Kerikeri were smashed in what Mr Carter said looks like a targeted attack.
Mr Carter said apart from the cost, the vandalism poses a huge risk to the travelling public, and it is only a matter of time until someone is injured or killed due to the absence of warning signs.
He is appealing for anyone with information about the vandals to tell the council.