A Kiwi cop helped catch an American paedophile who was jailed this week after amassing a huge collection of violent child abuse image.
The FBI said Chad Michael Rein, 27, of Kansas City, was sentenced this week to 10 years in federal prison without parole.
The investigation began in May 2012 when a New Zealand detective was working undercover in a peer-to-peer, file-sharing network.
"He downloaded multiple images and videos of child pornography from Rein's computer. That information was forwarded to the local FBI Cyber Crimes Task Force and a search warrant was executed at Rein's residence," the bureau said in a statement.
Child sex abuse images were found on a desktop computer and external hard drive seized during the search.
The FBI said court documents showed Rein collected thousands of images and videos of child sexual abuse imagery, including images of toddlers being sexually violated.
"The recurring theme in his collection was the violent and overwhelming application of sexual force by an adult on a restrained infant child," the FBI added.
At the time of his arrest, Rein lived with two sex offenders and worked at a restaurant located across the street from a pre-primary school.
The FBI said its Cyber Crimes Task Force worked with Kansas City police and New Zealand Police to investigate the case.