During the next 10 days, Oamaru police will crack down on teenage drivers failing to adhere to restricted driver's licence rules, as part of an ongoing road-safety blitz.
Acting Sergeant Ewen Graham said the campaign, which runs until June 17, would target motorists on both learner and restricted licences, as well as cyclists failing to wear helmets.
The actions of restricted drivers in particular were becoming a concern Acting Sgt Graham said.
"We get a lot of drivers failing to fully comply with licence restrictions. A lot of them are young drivers carrying unauthorised passengers."
Restricted driver's licence rules mean a restricted driver could not carry unlicensed passengers without a fully-licensed supervisor, which meant that many youngsters giving mates a ride into town after passing the restricted licence were often breaching the conditions of their licences, he said.
Restricted drivers were also prohibited from driving without a supervisor between 10pm and 5am.
Since the start of Operation Breach on May 28, police have recorded 14 breaches of both learner and restricted licences, and three cyclists riding without helmets.