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."
More top news
On ITV News at Ten this evening, an incorrect picture was used in a story about Edwin Mee, who was found guilty of 13 sex attacks...
Europe is at risk of an unprecedented explosion in obesity rates, researchers say.
Windy, wet weather whipping us up