Police are working to establish when the vehicles, at Awamoa Park, were targeted. The incident was reported to police on Wednesday morning.
Sergeant Blair Wilkinson, of Oamaru, said a ute and car were both forcibly entered and attempts were made to start them, which were unsuccessful.
Both vehicles were damaged on their driver’s side doors and ignition barrels.
However, police were not ruling out the possibility the offender or offenders did leave the scene in a stolen vehicle.
"We ask people to check their vehicle is there and that it has not been broken into."
Over the past several years vehicles have repeatedly been targeted by vandals and thieves at the park that borders State Highway 1 in south Oamaru, prompting police to issue public warnings about the risk of leaving vehicles parked there.
While police could not force people to take their vehicles home each night, the public needed to decide for themselves whether it was worth the risk, Sgt Wilkinson said.
"There is a measure of inconvenience to collecting a vehicle from there each evening, but if people are determined to leave their cars there overnight they run the risk of these kinds of things happening.
"Anybody who has had their vehicle broken into up there, we ask they contact police on 105 so they can report it and we can get an accurate picture of offending in our area and it can be investigated alongside these other vehicles."
Eight vehicles were parked for sale yesterday, but there could be up to 20 vehicles for sale there at any given time.
In June, Sgt Wilkinson told the Otago Daily Times police had discussed the possibility of CCTV being installed to monitor the area with the Waitaki District Council in the past, and remained open to the idea, if both parties agreed it was appropriate.
