Police are warning buyers to be vigilant after a spate of bike thefts resulted in them surfacing for sale online.
There have been several bike thefts in Christchurch over the past few weeks, police say.
Two people "responsible for a large number of the thefts" had been arrested, Detective Senior Sergeant Damon Wells said, and other thefts were being investigated.
"The majority of these stolen bikes are being sold via Facebook Marketplace, and police would remind people to take care when purchasing online," Wells said in a statement today.
"We'd recommend you purchase from authentic sellers and genuine retailers, and websites based in New Zealand.
"If you're purchasing from an individual, we suggest you request proof of ownership, or perhaps some form of ID.
"If the seller is not able to or refuses to provide these, it's possible the item may be stolen."
He added: "Generally speaking, if the deal is too good to be true, it often is."
Police say if you own a bike, ensure you record the serial number, keep a copy safe, and upload to www.snap.org.nz
If you purchase a bike, ensure you record these details as well.
Police say people should also consider a high-quality D-lock or similar to deter would-be thieves.