Yokohama, Japan (IPS) feature - The Internet remains a major tool used for the sexual exploitation of children across borders, but cyber sleuths at a global congress here say they are learning to get to know to the enemy - and making an ally of this double-edged technology.

''Our message to sex offenders is we're here, and as long as you're out there, we'll find you,'' said Sharon Girling of the National Crime Squad in Britain. ''We're winning the war.''

This is despite the rise in child pornography and the use of the Internet by abusive adults and trafficking groups in recent years, and what some experts say is a growing link between the easy access the Internet offers and sexual interest in children.

Indeed, images of children being abused are appearing on the web and being distributed in public much quicker than before, when it took five to 10 years after photographs were taken before they were circulated, according to experts at the Second World Congress against Commercial Sexual Exploitation of Children here.

But Hamish McCulloch, a specialised officer with Interpol based in France, said that while ''this is a young criminal area we're dealing with,'' the skills and capacity of law enforcers are fast catching up with that of offenders, who years ago thought they could remain completely anonymous on the World Wide Web.

Images database

In September, Interpol developed a database of images of abused children on the Internet, one that is available to the organisation's 179 governments and can be used to hunt down child sexual abusers around the world.

The database allows Interpol to help governments access updated information on images of sexually abused children distributed on the Internet. It has ''image comparison software'', developed by a Swedish police officer, to link different abusers as well as track multiple victims.

''Until this arrived, there was a lot of duplication of efforts'' by governments, McCulloch explained at a briefing here.

For instance, if police find web pictures of two children being abusedin a hotel bedroom, that would go into the database. Governments could use the hotel picture to try to track its location, and see if it yields clues to indicate the location of the offense, or the offender.

But there are problems, among them the difficulty of tracking sex abusers or victims from pictures that often could have been taken in virtually any place in the world.

''Even after you have identified new pictures, then what? Working from pictures is extremely difficult, many pictures do not show evidence of location,'' said Max Taylor of the University of Cork in Ireland.

McCulloch agreed that there are limitations on pursuing cyber sex offenders - Interpol is not an investigating body and focuses on the facilitating the exchange of information and intelligence, based on requests by governments.

Likewise, he and other experts agreed that few very governments have the resources to do international operations to collar offenders, and many of these countries are in industrialised countries like Germany and Norway.

But when some governments do use the resources they have, Girling says, it can yield important results, citing the example of how facial recognition software used by Britain helped secure the conviction of a paedophile. A girl had said a man sexually abused here and police used this software to locate an uploaded picture of her - one that was accepted in court.

But police work alone is far from enough in following sex offenders around the world.

Tip of the iceberg

Experts and activists called for laws in different countries to go after sex abusers and make it harder for them to operate, and asked Internet service providers to show more willingness to act against child pornography and the use of the web for the sex trade in children.

''Trafficking in children is becoming as big as the trafficking of drugs, but the penalties for it are so much smaller,'' explained Carole Howlett of the serious crime group of the Metropolitan Police Service in London.

McCulloch said that web images of children are actually just the tip of the iceberg, since most sexually abusive pictures are in privatecollections and distributed quietly. ''But still, some countries have laws and others don't,'' he said.

John Carr, associate director of the children and technology unit of the non-governmental NCH Action for Children, says that the sentencing of cyber sexual offenders needs to be harsher - Britain, for instance, has no legislation dealing explicitly with trafficking.

Legislation is also one of the options for regulating Internet service providers, and getting them to cooperate by, among others, keeping information on sites accessed by users for longer than just a number of hours.

''The Internet service providers could do more much more here, or at least show much more willingness to cooperate,'' said Taylor. The short storage period of data by Internet providers means that by the time authorities reach them during in inquiry, the data about the web activities of those habitually accessing pornography and related sites are lost.

Girling added that it is illegal for authorities to just shut down Internet service providers who consistently allow access to pornographic sites, but they can take action against persistent perpetrators.

ISPs resist controls

There is software in Britain that allows law enforcement agencies to attach to the service providers' servers sexually abused images of children from the web, and bars access to them, she said.

Often, she added, Internet service providers resist controls because they believe it is bad for their business. Others say that debate on access to information may also emerge in this case.

But despite continued activity by Internet offenders, law enforcers and child rights activists agree that efforts to track them down have to continue on an international scale, and combine the best of technology, laws, lobbying and understanding.

McCulloch argued, ''We have learned that it is global problem and territorial issues and concern with geography will hinder the response to this problem. We need new institutions, large-scale mechanisms to enable the sharing of knowledge and both police work and understanding of the issue.''

Likewise, Nigel Williams of Childnet International in Britain says, law enforcers need to be vigilant because ''new technologies are emerging allthe time'' that paedophiles and sexual offenders use and may try to spread to different parts of the world.

He pointed to the emergence in Japan last year of the use of the latest mobile phones to link to the Internet dating clubs, which soon found young girls getting into sex with older men.

''Child prostitution going to the Internet in Japan is new, it's part a culture issue, a technology issue, but this problem and chatroom environments in mobile phones is something we have to be prepared to respond to (in other places),'' Williams added.

Malaysiakini is running a series on child sexual exploitation starting yesterday in conjunction with the Second World Congress Against the Commercial Sexual Exploitation of Children, which is currently being held in Yokohoma, Japan.