A rooftop raider stole around $200,000 worth of jewels in a Christchurch store break-in during the weekend.
The burglar, or burglars, stole from the La Bu jewellery in the Tannery shopping complex on Sunday morning, police told Fairfax.
"I'm just imagining someone did a lot of scoping before they did the crime," Tannery owner Alasdair Cassels told Fairfax.
"If you looked at how they got in and where they got in, they must have known rather well the layout of the shop."
They ripped off a sheet of corrugated roofing iron and broke through the ceiling above an adjacent store before punching a hole through a wall into La Bu.
About 2000 rings were stolen, each worth between $50 and $200, costing the owner $200,000.
"It has happened in the past, it's not unheard of, but we've had a few more lately," Detective Sergeant Damon Wells told Fairfax.
Police were reviewing CCTV footage but it was not yet clear if more than one person was involved.