Damage to 35 cars at a Balclutha auto spares workshop is the latest in a string of vandalism incidents in the South Otago town.
Vandals broke into Munro Auto Spares on High St four nights in a row this week.
Police said people had jumped on vehicles, damaging windscreens, panels, side mirrors and headlights.
The vehicles were stored outside in the yard.
Sergeant Martin Bull, of Balclutha, said it was not the first time the business had been targeted.
Other incidents had occurred there in the past month, as well as vandalism in other places.
"Due to the proximity and similar type of nuisance stuff ... I think they're linked.''
The rate of incidents increased this week, he said.
He believed it was likely a group of three or four people was responsible.
Munro Auto Spares director Kevin Munro said those responsible had directly affected his livelihood.
The interior of the vehicles were now exposed to the elements.
"It ruins the stock completely. I'm bloody frustrated.''
He would like to "wring the necks'' of those responsible, and suspected young people were to blame.
The worst damage to his stock was done on Wednesday night.
He was disappointed those responsible had not been caught.
He was insured.
Other incidents included a window smashed at the former Balclutha railway station and faeces smeared on the walls at Rosebank School.
Sgt Bull said it was concerning someone was causing persistent trouble in the same area.
"If we are unable to find out who they are, they'll get bolder.''
Residents needed to be more aware there were people roaming around the area causing damage.
He asked anyone who saw anything suspicious to call the police immediately.
