Two recent thefts of diesel in Napier suggest some thieves have found an alternative to siphoning.
Trucks parked in the Onekawa industrial area, one in a yard off Ford Rd and one off Leyland St, were targeted recently and Constable Mike Burne said the thieves carried off more than just the diesel: "They took the tanks."
Both incidents took place during the same weekend.
Thieves first struck at the Ford Rd yard, and Mr Burne said the methodology employed almost certainly showed the same offenders were involved in both incidents.
Rather than try to drain the tank they removed the complete unit.
In Leyland St, a hole was cut through a fence to gain access and the thieves removed a 50-litre diesel tank by undoing the heavy gauge straps holding it in place.
Given the potential weight involved, Mr Burne said at least two people using a vehicle able to transport a large tank would have been involved.
Fuel thieves also targeted a vehicle parked on a display ramp at a car sales yard in Pandora.
The approach was basic - they punched a hole in the tank and drained the fuel.
Scrap metal had also been a popular target for thieves in the industrial areas, Mr Burne said.
Police had got a good result after one incident, he said.
They were able to pick up a man who they said had been involved in scrap-metal thefts in Onekawa last year.
A night patrol came across the man after scrap-metal yards in Austin St and Cadbury Rd had been entered and items taken. As well as facing two counts of theft, the man was also charged with the burglary of a central Napier business on the same night.
Mr Burne said the accused had instruments that were clearly used to carry out burglaries.
"We have had a couple of good resolutions relating to scrap-metal burglaries," Mr Burne said.
Scrap metal would continue to be a popular target for thieves: "If you have loads of scrap around your yard, I'd suggest you consider doing something with it."
Scrap attracted the "magpies" and while they were eyeing that, "they'll also be checking to see what other shiny items you may have".