THE horror of the missing Belgian girls has opened another file for international detectives investigating the worldwide paedophile network.

The perverts protect each other through a sophisticated computer system intended to give them ``safe'' access to victims. And if they do get into trouble with authorities, the same system puts them in touch with sympathetic lawyers who are skilled at finding loopholes in the court system. Some, contactable by passwords on the Internet, charge exorbitant fees for their dubious expertise.

Offenders also barter on the Internet by trading photographs for false identification, usually driving licences. This allows a paedophile convicted in Florida of operating in California - and even being arrested there - under an assumed name. By the time the authorities realise the deception, the courts will probably have granted the offender bail. And he will be gone.

Offenders and their lawyers know how quickly to work the cumbersome legal system.

The hi-tech extent of this sex war on children was highlighted in the American best-selling novel The Poet. Author Michael Connelly, a former police reporter with the Los Angeles Times, turned known fact into fiction. Readers were upset and shocked by the tactics of the child pornographers.

But Connelly used up-to-date data in plotting his story about the hunt for a serial killer who is also a paedophile. He also disclosed the counter measures being taken by American authorities.

The FBI Behavioural Science Unit in Washington has vast lists of convicted paedophiles, and of others it believes are offenders. But it admits that the matching of abuse to perpetrator is becoming more and more complicated. The same is true city

by city despite the fact

that Exploited Child Units have increased facilities and manpower.

More and more victims are being snatched or kidnapped, abused, and then abandoned. Or, as in Belgium, killed. Offenders can be in another city or state before their crimes are discovered.

Cunning paedophiles make contact with each other on cellular telephones so that calls cannot be traced. On the Internet there are ``notice boards'' where messages are left. Generally, it acts as a contact system for circulating child pornography. There have been some cases of ``snuff'' images - children being killed while being photographed or filmed on video. But increasingly there are also computer ``escape routes'' for violent offenders who kill or maim their victims.

``It's like a club,'' says an FBI spokesman adding: ``They truly understand each other and what drives them and because of that they can plan ahead. They know what they want, what they need. Of course, we get random outrages but more and more it is premeditated. Contacts are made, situations appraised, and then an individual or a group will act.''

The number of paedophiles in America is estimated in the many tens of thousands. In the UK the number is said to be more than 50,000. Dunblane killer Thomas Hamilton had photographs of young boys and computer equipment at his home. Amsterdam and Manila are seen as paedophile ``hubs'' circulating pornography and ``advice'' worldwide.

Interpol and the FBI looking into Internet pornography have made several arrests in past months but nothing to dent the international scale of the 21st-century perverts.

It is scarcely surprising that the world is horrified as the sickening events in the tiny southern Belgian village of Charleroi continue to unfold, bearing as they do an uncanny similarity to the only too recent grisly goings-on at 25 Cromwell Street, Gloucester.

Just a handful of stories that have appeared in the British press recently bear out the view of police forces worldwide that the multi-million-pound international business of paedophilia can now cross borders much more easily.

First of all Dunblane. Whatever Lord Cullen concludes, there is one thing of which he will be certain. Hamilton bore all the signs that he was a

paedophile, and it was this which set him off on his murderous spree. It is only a few months since Robert Black, killer of Susan Maxwell, aged 11, Caroline Hogg, five, and Sarah Harper, 10, had his appeal against 10 life sentences thrown out.

The West trial is still far too fresh in everyone's mind not to recall the horrific recorded rapes of daughter Ann Marie and the circumstances in which other girls and young women died. So, too, is the inhumane and callous kidnapping and rape of nine-year-old Daniel Handley. He was picked up because of his fair hair and blue eyes when two perverts came across him out playing on his bicycle.

The parents of murdered schoolgirl Sophie Hook, taken from a tent in her uncle's back garden before being raped and strangled and thrown into the sea, reflected on the past sexual history against children of her killer Howard Hughes: ``She was the trigger for that particular timebomb and it didn't need to be like that.''

The police had watched him for 16 years, but he struck and their daughter was the victim.

Then we have the case of Caroline Dickinson, murdered in France on a school outing.

Paedophiles read these stories and they get a lot of satisfaction out of them. Not all of them are driven to murder, but

for a percentage that is the ultimate thrill.

Children in care have been proven to be easy victims. This is one form of paedophilia and it goes on all the time. Mostly those abused are too innocent or too ashamed to talk about it, or they believe threats that reprisals will be taken against those closest to them: ``Your mother will be poisoned'' . . . or ``your dog will die''.

In this group, most of them feel that it was their fault . . . they were the ones to blame. Unfortunately in later life they can turn out to be abusers.

The great danger is that once a paedophile always a paedophile, no matter what good meaning psychologists say. There is the case of an individual in England who persuaded doctors to castrate him after a lifetime spent in prison. He was even given a certificate saying he was no longer a danger to young children.

Despite the operation young children later were taken into local authority control because of his influence over them.

They come from all sections of society. They will use any form of guile to fulfil their fantasies. They even boast that no matter what measures the authorities come up with, they will find a way around them.

Terms spent in prison are well worth it in the knowledge that on release they can carry on with their chosen life. It is certainly not unknown for recognised paedophiles to have assaulted well in excess of 100 children in a lifetime. In fact that might be seen as an under-estimate of the problem.