Whanganui police are urging rural residents to report any suspicious vehicles or activity on their roads.
The warning comes after a burglary at a Makirikiri Valley Rd property near Upokongaro this month in which jewellery was stolen.
"The occupant heard a vehicle come up the driveway about 2.30pm on March 2 but didn't see it," Senior Sergeant Shayne Wainhouse said.
"She didn't think much of it but later discovered a couple of rings and a bracelet were missing."
Mr Wainhouse said it was not known whether the vehicle was linked to the burglary but it was a reminder to rural residents to be alert.