Internet search giant Google has helped convict two New Zealand men on charges of possessing child pornography, China's Xinhua news agency reported New Zealand's Department of Internal Affairs as saying today.

Google detected the two men separately uploading objectionable images and reported them to New Zealand authorities, said a statement from the department.

Inspectors traced the offenders and found incriminating material on their computer equipment.

The men, aged 46 and 52, were sentenced in courts in Auckland this week to periods of home detention.

Censorship compliance inspector Jon Peacock said the department was part of a worldwide network of law enforcement agencies committed to helping prevent the abuse of children.

"We have the expertise to track down offenders who may think, quite wrongly, that they're safe in the confines of their own homes," Peacock said.

"Trading or viewing these images is not passive offending because it condones the abuse children suffer. People, who look at this material, pass it on and use it, encourage those who actually photograph the children."

The announcement came as the government said it would be establishing the country's first child sex offender register.

"Children deserve to be kept safe from harm, which is why we are going to be more proactive in managing the risk of reoffending from child sex offenders," Social Development Minister Anne Tolley said in a statement today.

"Currently, these offenders can disappear back into communities when they have completed a sentence or order."

Offenders would be required to be on the register for a term of life, 15 years or eight years depending on their offence and the sentence imposed.

The register would include New Zealand offender and offenders who moved to New Zealand after being sentenced to imprisonment for a corresponding offence or subject to registration requirements for a corresponding offence in another country.

Police estimated the register would initially list about 1,750 people in total.

- Bernama