Peter Davies, head of the Child Exploitation and Online Protection Centre (CEOP), said there was now a "class of child abusers very proficient in technology" who are consistently trying to evade authorities by finding new means of accessing children.
Speaking to Daybreak, he said: "The old model, with a view of meeting online with a view to meeting offline and then physical abuse taking place is actually a diminishing, these days sexual abuse of children can take place purely online."
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