NZ children caught in exploitation ring

Two New Zealand victims have been caught up in a massive international pornography ring, police say.

The online child exploitation ring dismantled in the US, dubbed Operation Roundtable, has been linked to victims in Australia and New Zealand.

The organisation is "one of the largest-known online child exploitation operations in history", US Department of Homeland Security chief Jeh Johnson told reporters on Tuesday.

Online Child Exploitation Across New Zealand (Oceanz) detective Senior Sergeant John Michael said United States authorities found New Zealand children were victims of the US-based group.

"We subsequently identified two young male victims in New Zealand, aged 12 and 13, that had been exploited and were able to take steps to ensure their safety," he said.

"This investigation highlights the fact that the internet allows predators to exploit children around the world, even in the safety of their own homes," Michael said.

"The high level of co-operation during Operation Roundtable demonstrates the willingness of international law enforcement agencies to combat online child exploitation."

US authorities arrested and charged 14 suspects in the secret, members-only online network, which had more than 27,000 subscribers.

New Zealand Police said no New Zealanders were being sought or questioned about the matter. 

All the men arrested were based in the US, police said.

The website's 250-plus underage victims lived in five countries and in 39 US states, officials said.

Most victims were boys aged between 10 and 17.

Among the countries where victims were found were Australia, New Zealand, Great Britain, Canada and Belgium.

Among the suspects taken into custody was Jonathan Johnson, 27, the administrator of the website, which operated from the southern US state of Louisiana.

If convicted, Johnson faces 20 years to life in prison, Kenneth Allen Polite, US Attorney for the Eastern District of Louisiana, said.

"These indictments represent a strong co-ordinated strike ... against child pornography and those who allegedly seek to harm our most vulnerable citizens, our young children," Polite said.

The illicit website operated on a hidden service board on the Tor network from about June 2012 until June 2013, when Johnson was arrested.

The Tor network is set up to conceal user's identities, search habits and locations, ensuring online anonymity.

Authorities said at the time it was dismantled, the illegal website contained more than 2000 shared webcam-captured videos of mostly juvenile boys enticed by the website's operators to produce sexually explicit material.

The investigation, which officials said is continuing, was carried out by DHS and the cybercrime unit of Immigration and Customs Enforcement, and the US Postal Inspection Services.