Hundreds of thousands of young people are being subjected to cyberbullying, with many being victimised for a year or more, new research suggests.

The Beatbullying study, based on a survey of 4,605 children and young people in the UK, found that just over one in four (28%) 11-16-year-olds say they have been the victim of cyberbullying.

Cyberbullying is the bullying of another person through technology, such as mobile phones or the internet.

In more than a quarter of cases, the individual concerned was continuously targeted, suggesting that one in 13 secondary school children have faced persistent cyberbullying, the report claims.

The latest Virtual Violence II study says that with around 4.38 million secondary-aged children in the UK, it means that around 350,222 children have been the victim of persistent cyberbullying.

The study, which was commissioned by Nominet Trust and backed by the National Association of Head Teachers (NAHT), reveals that the effects of cyberbullying are far-reaching.

A fifth of victims said that fear of bullies made them reluctant to go to school, while 19% said their confidence and dropped and 14% said they did not feel safe.

In addition, 5% said they had resorted to self-harming and three percent admitted they had attempted suicide.

And it is not just young people that have been the victims of cyberbullying - the study, published to mark Safer Internet Day, found that one in 10 teachers say they have faced cyberbullying and almost half of the 339 teachers questioned (48%) said they have heard or witnessed colleagues being harassed.

Beatbullying chief executive Emma-Jane Cross said: "Cyberbullying continues to be a dangerous problem for a significant number of young people and we must not ignore its complex and often devastating effects. An integrated approach where we see Government, schools, parents, internet service providers and charities like Beatbullying all working together to keep our must vulnerable safe."