Videos depicting children being sexually abused for more than two hours have been seized by Australian Federal Police who have arrested 19 men over the child porn ring.
Police say images on some of the videos are among the worst they have ever seen.
Australian Federal Police (AFP) have identified 22 men across NSW, Victoria and Queensland following a 12-month investigation into an online child abuse image and video-sharing network.
Child protection operations teams seized more than 15,000 videos and 500,000 images of child abuse which were shared between members of a peer-to-peer network.
The images and video included the sexual abuse of children as young as 12 months old.
Police so far have executed 28 search warrants which have resulted in 19 men being arrested and three other matters being pursued through other court processes.
The operation began when the AFP received a referral from the Brazilian Federal Police in December last year.
The information assisted federal police to identify a number of alleged offenders found to be sharing videos and images depicting child sexual abuse on the internet.
The operation removed at least two children from harm, acting deputy commissioner operations Andrew Colvin said.
"The videos seized as part of this operation have to be among the worst we have seen.
"Some depicted sexual abuse of children lasting more than two hours."
Mr Colvin said the viewing and exchanging of child abuse material would not be tolerated in Australia.
The AFP, with its state, territory and international counterparts, would continue to fight the "repulsive" crime.
"If we are not knocking on your door this morning, then it could be tomorrow," Mr Colvin warned.
The internet should not be regarded as an anonymous place because it was just another place for police to patrol, he said.
AFP acting assistant commissioner Neil Gaughan, national manager of high-tech operations, said further arrests could be expected in the next few days.
Most of the abused children came from eastern Europe and North and South America.
Information from Brazilian police indicated that 200 men from more than 70 countries were trading the material through a peer-to-peer network.
That allowed them to share files without going through a central network server, avoiding filters operated by the internet service providers and keeping out those not involved in the network.
"Law enforcement does have tools, so we can get in and infiltrate these type of applications," he told ABC Radio.
Concerns about suspicious and/or inappropriate behaviour can be reported online through www.virtualglobaltaskforce.com or to your local police.
Meanwhile, a Sydney man charged in connection with the child pornography ring will also face child sex charges after allegedly having intercourse with a 13-year-old girl on several occasions.
Richard Ngong Fung Lee, 24, was arrested at his Blakehurst home on Wednesday after allegedly accessing child pornography on his computer.
Lee on Thursday appeared in Sydney's Central Local Court, where his case was briefly mentioned before Magistrate Allan Moore.
He faces two child pornography charges and six child sex charges.
It is alleged Lee had sexual intercourse with a 13-year-old girl over a 17-month period from April 1, 2007 until September this year.
On one occasion he gave the girl alcohol, the charge sheet alleges.
No further details of the allegations have yet been tendered to the court, and a balance of a brief is to be filed by January 28.
Lee is due to face the same court again on December 17, when his lawyer Daniel Sheen said he might apply for bail.