A Department of Internal Affairs investigator whose work led to the discovery of an international child sex trafficking ring says he doesn't believe the scale of the abuse is unique.
The case involved an Australian man who bought a baby boy for $US8000 with his partner, sexually abused the child and handed him to other paedophiles to molest.
The man was sentenced in the United States on Friday to 40 years' prison. His partner has pleaded guilty and will be sentenced later this year.
The international prosecutions began when Internal Affairs investigator Jon Peacock noticed something suspicious about a series of photos of a six-year-old boy stored on the computer of a New Zealand man in a separate investigation.
Mr Peacock said the way the boy looked into the camera and the poses in the photographs made him think something may have been badly wrong.
Using clues to the boy's identity from photographs and video the investigation team linked the case to Queensland and involved Australian enforcement colleagues.
Prosecutors eventually discovered videos and photos of the man, his partner, also an Australian man, and other men in Australia, the US, Germany and France abusing the child from the age of two to six, AAP reports. The boy was rescued by US authorities and is being cared for in California.
Mr Peacock told Radio New Zealand's Morning Report programme that while this case was extreme in terms of the degree of premeditation and global organisation, he believes similar offences are being carried out by people who are financed and organised enough.
He says very few children who are the victims of such abuse come forward, so law enforcement agencies around the world have to be aggressive and creative in how they investigate.
Mr Peacock says the Department of Internal Affairs unit punches above its weight in uncovering these crimes, but could do a lot more if it had more resources.
An organisation working to eliminate child sex abuse says the crimes being committed are becoming more extreme, and the victims younger.
The director of ECPAT, Alan Bell, says while the Department of Internal Affairs is at the forefront of efforts to crack down on internet child porn traders, it only has 13 investigators, and it needs more resources.
Internal Affairs Minister Chris Tremain believes the department is well resourced, saying New Zealand investigators were involved in Operation Laminar two years ago which resulted in about 40 arrests internationally.