In a slum on the Philippines island of Cebu, local police have come to rescue two girls.

Key points: Advocates want greater cooperation from telcos over cyber sex abuse

Advocates want greater cooperation from telcos over cyber sex abuse In 18 per cent of cases, telcos aren't handing over information requested by AFP

In 18 per cent of cases, telcos aren't handing over information requested by AFP The abuse is becoming more violent and the victims are getting younger, police say

They've been tipped off by the Australian Federal Police (AFP) that the girls' mother has sent 164 sexually explicit images of her daughters to an Australian man using the Viber messaging app.

The mother was allegedly paid about $800 in return.

When Philippines police arrive at the home, a 15-year-old girl is undressing in front of a webcam.

Three days later in the troubled Mindanao region in the south of the country, another raid begins.

This time explicit footage of four children aged between two and 13 is being streamed live over the internet.

The Philippines National Police is referred more than 6,000 cases of cyber sex abuse each month from around the world.

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'It's difficult to get the evidence'

Sorry, this video has expired Police raid a pay-per-view child sex abuse session in Mindanao, Philippines

Pay-per-view child sex abuse is increasing, and it's believed thousands of Australians are paying to watch a range of sexualised footage in real time.

The AFP says it is grappling with a "tsunami" of reports of all kinds of sexual abuse and violence against children.

So far this year the AFP has received 4,937 reports of child exploitation.

Chief Judge of the Federal Circuit Court, John Pascoe, has argued for greater cooperation from telcos such as Telstra to help track down the perpetrators.

"We're talking about the most extreme forms of abuse, where there are some examples where people have been wanting to see, for example, the violent rape of children, five, six, seven years old," he told 7.30.

"It's difficult to get the evidence that someone has been watching this sort of material.

"It needs a lot of co-operation between law enforcement authorities, internet service providers and telcos."

The AFP said it has a good working relationship with the telecommunication companies, but there are worrying limitations.

7.30 can reveal that in 18 per cent of cases, Australian telcos are not providing the online information that police request.

According to AFP commander Lesa Gale, when a telco fails to provide sufficient information, the investigation "stops, it ceases, it means we can't do anything more".

Police often request subscriber records or mobile data from the telcos to track down offenders.

"The abuse is getting more and more violent, the children are getting younger and younger," Commander Gale told 7.30.

"The requests are becoming more and more extreme, as if it was almost a competition between offenders and producers to try and make more and more extreme material depicting horrendous acts occurring on babies and young children."

Laws not keeping pace with technology

A Filipino police investigator takes a picture of the computer of a suspected child exploitation operation. ( AP: Aaron Favila )

Chief Judge Pascoe is worried the law is not keeping up with the pace of technological change.

"I think if you look at large corporations, they're made up of many people, employees, shareholders and I think the public does have a right to expect that they will be part of the social contract," he said.

"They will be aware of Australia's obligations and they will do their part to protect children."

He argues that companies have an obligation to protect children at home and abroad under the United Nations convention on the Rights of the Child.

"The law actually needs to recognise the true nature of the crime and give the police the powers they need to appropriately prosecute offenders," he said.

"And I think one of the problems in this area, there somehow seems to be a disconnect between sitting at the computer typing what you want to happen next to the child and actually doing it.

"To me there is no distinction."

Mark Leach, a board member with International Justice Mission Australia, said telecommunications companies have a moral obligation to assist.

"It's our view that the directors and management of any telco in the country would be appalled that their company assets and their business were being used to commission and perpetrate the rape of children in the developing world," he told 7.30.

The AFP said requests might not be fulfilled for a number of reasons, including "the fact that investigators, at times, need to put requests to all major telecommunication companies, knowing that only one of the telecommunication companies would be able to complete the request".

Both Optus and Vodafone told 7.30 they comply with their legal obligations to assist police.

An Optus spokeswoman said: "We have responded to every request we've received from law enforcement agencies this year. There are no requests where we haven't provided some form of response.

"There are circumstances where we have advised law enforcement agencies that we are unable to provide information because we don't capture the specific piece of information requested. There are also some instances where we've asked the AFP to resend a request under the correct part of the legislation."

Telstra said it responds to tens of thousands of requests for customer information. It said it supports law enforcement while protecting the privacy of its customers.

"We take very seriously our legal and regulatory obligations to assist law enforcement agencies who are seeking information," a Telstra spokesman said.