Police have been making more arrests lately for suspicious activity thanks to help from the public.
Senior Sergeant Andrew McDonald said there had been a rise in suspicious activity in the area between lower St John's Hill and Aramoho over the past month.
"We've been deploying extra patrols in those areas to try and deal with the activity in that area," he said.
"We've actually had some good arrests or catches for people interfering with cars and being unlawfully on a property, really thanks to the awareness of the public."
People calling the police whenever they saw "just suspicious behaviour in general" was helping, and police wanted people to continue making calls with "good descriptions and locations".
Mr McDonald said overall levels of suspicious activity in Whanganui had not risen.