Thieves are targeting custom-made car transporters and are thought to be using the vehicles to hide stolen cars.
Constable Aimee Brinsley said it was the first time she'd encountered the specialised trailer theft in eight years working with the burglary squad.
On Tuesday, Januray 21, thieves made off with two distinctive car transporters from a caryard on Hillside Road, Wairau Valley, North Shore.
The thieves ignored caravans and other vehicles nearby, making a beeline for the big trailers.
Two distinctive car transporters were stolen from "U Sell" Car Yard between 2.30am and 8am.
"The trailers appear to have been targeted as other high end vehicles and caravans were not taken. Both of them were custom made and very distinctive," a police spokeswoman said.
No other high-end vehicles and caravans were taken.
Constable Martin Guest said he received another complaint on Friday relating to a stolen car transporter trailer, taken sometime between January 24 and 31. It also was custom made, painted black, with a single axle and car ramps attached to the sides for transport. It was taken from a commercial premises in Beach Haven.
Police asked the public to call 111 or Crimestoppers on 0800 555 111 with any information on the trailers.