The organisation wants a more systematic approach to investigations, pointing to the fact that many cases of sexual abuse against children are uncovered by accident.

The NSPCC says investigations into paedophiles are frequently hampered by a lack of information sharing between relevant bodies, such as the police, local authorities and children's groups.

Highly organised

Children are often reluctant to come forward, the society says, and paedophiles compound this by targeting groups that find it difficult to report crimes, for example, ethnic minorities where members do not speak English

Child sex offenders can also be highly organised and will rely on each other to intimidate witnesses and destroy evidence of their activities.

The report attributes most investigations to chance sharing of information between agencies, to abusers informing on each other, or to disclosures by victims who have been apprehended committing frequently unrelated offences.

New guidelines

The NSPCC has responded by issuing new guidelines to groups that tackle child sex abuse.

They include proposals for the systematic sharing of information on all reported cases, joint investigations between social services, children's groups and the police, a programme of tracing victims and offenders and the establishment of specialist liaison teams.

NSPCC Director Jim Harding said: "Organised abusers are single-minded and relentless in their abuse of children."