Teenage girls are being used as "honeytraps" to lure older Christchurch men.
Gangs are using women as young as 16-years-old to target unsuspecting men who are then being beaten, kidnapped and robbed.
The tactic is called "honey-trapping".
Police say women are reaching out to men online, arranging to meet with them, then the gangs step in.
They say a 45-year-old man picked up two 17-year-olds from a Woolston address in late December, before being beaten and robbed of his car, cellphone and wallet.
Police are investigating another incident, but say it's only a "small part" of gang communities.