Parents are being urged to make sure their children are safe online using new smart phones and games consoles they got for Christmas.

Sarah Lambley, NSPCC community fund raising manager for Cambridgeshire said: “We know children are becoming increasingly concerned about what they sometimes encounter on the internet from the increasing number of calls on the subject to our Childline service.

“Over the past three years there has been a 33 per cent increase in the number of counselling sessions held with children about online sexual abuse they have been subjected to.

“Some children contacted Childline because they felt trapped and ashamed by their situation and were too were frightened to talk to an adult.

“Some were being blackmailed, while others wrongly felt they were to blame because they have participated in their abuser’s actions.”

She added it was vital parents talk to their children about being safe online, spotting the signs of inappropriate behaviour, and how to report it.

“Online sexual abuse can take the form of grooming, child sexual exploitation, sexting, being made to perform sex acts on webcam, meeting up in person, and viewing distressing sexually explicit content.”