A child advocacy group says there has been an increase in sex abuse involving technology such as mobile phones.
Two teenagers pleaded guilty in the High Court in Auckland on Friday to sexually abusing a child under 12, recording the abuse and posting the images on the internet.
Stop Demand, which campaigns against child exploitation, says mobile phones and the internet have made it easier for online predators to access explicit content.
"You have behaviours in society that weren't there in the same way as they were in previous decades, for example 'sexting'," says founder Denise Ritchie.
She says she thinks young people may have trivialised such offending.
Ms Ritchie says the sexual violation of a child is one of the most heinous crimes and causes long term damage.
She says putting the crime on the internet means the child is abused repeatedly.
"Victim impact reports show that when a child victim of online sex abuse reaches young adulthood, their knowledge that their abuse and degradation will be circulating for ongoing sexual arousal of countless predators around the world can be devastating, can by psychologically crippling," she says.