Wanganui residents suffered more than 20 burglaries last week and police believe they are linked.
Senior Sergeant Andrew McDonald said the "huge amount" of burglaries came "despite having a couple of arrests around incidents in the Gonville and Castlecliff area".
New areas being hit were St John's Hill and city/lower Aramoho.
Mr McDonald said it indicated there were a couple of groups involved. Many of the burglaries were happening overnight or early morning.
"In St John's Hill items being taken were electrical equipment and jewellery," Mr McDonald said.
Items stolen from the second area were mainly whiteware, such as dishwashers, and were being taken from vacant houses or homes for sale.
Neighbours needed to keep an eye out for anything, including people driving trucks up to houses and loading things in, he said, adding that police would rather be called out to find it was nothing than have another burglary reported.
He urged people to tell neighbours their movements and watch out for each other's property. People seeing suspicious activity should call 111. Anyone with information should call 06 349 0600 or Crimestoppers on 0800 555 111.
People should also record serial numbers of their property and distinctive features, damage or scratches. Numbers can be stored online at snap.org.nz to be accessed if anything is stolen.