Faster broadband, DSL and cable connections have contributed to an increase in paedophile activity on the Internet, the 19th Computer Facilitated Crimes Against Children Conference heard.

"Our caseload in this crime type has gone up 2,000 percent since we started in images in 1996," said the head of the American FBI's cyber division indecent images unit, Arnold Bell.

The increasing use of 3D mobile phones also posed a new threat as the next stage in the march of technology, he told reporters at the conference in the northeastern city of Brisbane.

"Technology continues to evolve and cell phones are the latest thing that pose some issues for law enforcement," Bell said.

About 100 delegates from Interpol, the FBI, the International Centre for Missing and Exploited Children and Microsoft are attending the one-week summit.

"Our primary focus, and I think the primary law enforcement focus, is to identify and rescue as many kids as we can," Bell said.

"I won't sugarcoat what we are talking about ... we're not talking about kids posing in their underwear. We're talking about penetration of children, some as small as four or five months old."

Bell said he remained optimistic about winning the fight against Internet paedophiles, despite a 2,000 percent increase in the crime in the United States alone in the past 10 years.

But Interpol representative Yves Rolland warned that paedophilia would never be wiped out, because of the growing number of ways to produce, store and exchange child porn.