Predatory paedophiles have been placed under intensive surveillance to prevent them from attacking children, the senior policeman in charge of child protection has told The Times.

Undercover techniques for tracking terrorist suspects and members of criminal gangs have been employed to follow some of the country’s most dangerous child sex offenders. Jim Gamble, head of the Child Exploitation and Online Protection Centre (CEOP), said that the surveillance operations – being piloted in five areas – had proved “a great success”.

For the past year CEOP tracker teams have been watching sex offenders who have been released from prison and are at risk of striking again. The pilot schemes have been extended and CEOP has asked the Home Office for the resources to make them available nationally.

Ministers may, however, be reluctant to commit to a large surveillance capability for CEOP. Human surveillance is labour intensive and expensive, and the recent history of other monitoring schemes, such as tagging and terrorist control orders, is littered with failures.

CEOP wants surveillance squads that could be dispatched when a police force sought help in monitoring a high-risk offender. Surveillance targets would be identified if changes in their behaviour or failure to abide by reporting conditions under the sex offenders register gave rise to concerns that they were about to attack a child. “Where you believe someone’s risk is going up, being able to watch them as we do terrorists, in the same way as we do organised criminals, ascertain their pattern of life, means that we are able to make judgments that protect our children much more effectively,” Mr Gamble said.

CEOP has strengthened its capability to police paedophile activity on the internet and believes that it is making the web a more hostile environment for offenders. This week it revealed how it had hijacked a paedophile ring’s chatroom, ensaring 700 suspects around the world and securing the conviction of Timothy Cox, the British head of the group.

Mr Gamble also urged parents to be more aware of the personal details that their children disclosed on MySpace, Bebo and other websites.

He said: “30 per cent of the children that we have reported to us aren’t at risk because a predator has approached them, they’re at risk because of the photographs they put up of themselves on their social networking sites.”

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