Channel 4 newsreader Cathy Newman has revealed that she was sexually harassed as a teenager at one of Britain’s top public schools.

At the time – in the early 1990s – Ms Newman was aged 16 and had just joined Surrey school Charterhouse’s sixth form on a scholarship.

In one incident, she said that a boy who was sitting beside her at lunch ‘unzipped his flies and grabbed my hand and forced me to touch his penis. I didn’t talk to anyone about it [for years].’

She also told how boys would spray her with water so they could leer at her through her wet clothes and described her regret at failing to blow the whistle on her bullies.

Channel 4 newsreader Cathy Newman (pictured) has revealed that she was sexually harassed as a teenager at one of Britain’s top public schools

Ms Newman, 44, added: ‘Now we’ve got online abuse and the [concern] about someone taking a naked photo… how much worse it would have been if it had been filmed and put out [online].’

Charterhouse said it had been unaware of her ‘serious allegations’ and had reported them to police.

She is one of more than 20 personalities and celebrities who have relived their childhood torment at the hands of bullies on video to encourage today’s pupils to speak out and seek help.

The campaign, launched tomorrow by the charity the Diana Award, includes new data on the scale of bullying that pupils tell researchers is affecting their grades, attendance and even forcing them to change school.

Some 28 per cent say they have been targeted by cyber-bullies, which gives them no escape even at home. Like many of those polled who say they have been bullied for being academic, Newman recalled being teased for being a ‘little girly swot’ who, at the age of eight or nine with her ‘neat little plaits’, was self-conscious about her ‘sticky-outy teeth’.

Charterhouse (pictured) said it had been unaware of her ‘serious allegations’ and had reported them to police

Newman said her degrading experiences meant that she ‘wasn’t very confident’ when she left Charterhouse, which now charges £40,000 a year for boarders.

‘Some of the things that went on at that school, I would now describe as sexual harassment,’ she told The Sunday Times.

‘I don’t know why I didn’t report them at the time.

‘If you wore a white T-shirt, the boys would get the fire hose out and spray you down so that they could see your underwear.

‘There were various more serious things that I really wish I had reported and I don’t know why I didn’t.

‘I think at the time, when you are at school, you just try to laugh it off.’

She said the experiences helped to shape her journalistic career, during which she has criticised ‘endemic’ sexism at Westminster.

‘As a woman in the media I feel a duty to make sure we report those issues. I’ve always wanted to right injustices,’ she said.