Instances of cyberbullying in Irish secondary schools have soared by a third in the last year, new research has found.
The number of pupils who admit to engaging in online bullying has also increased dramatically - almost doubling - according to the data published by the National Association of Principals and Deputy Principals (NAPD).
A survey commissioned by the association found that 16% of students claim to have been cyberbullied - this is up 33% on the rate in 2013.
The nationwide study, carried out by Amarach Research, found that 9% of students admit to cyberbullying another student, up from 5% in 2013.
The results have been published to coincide with the launch of the ISPCC's Anti-Bullying Month.
The survey is part of the NAPD's campaign to raise public awareness of cyberbullying and to help schools and parents to tackle the problem.
Other key findings include:
:: 26% of parents monitor their children's activities online on a daily basis, while 15% never monitor;
:: 64% of parents, under the age of 35, monitor their children's online activity weekly, compared to 40% of parents, aged over 45, who monitor their children's activity on a weekly basis.
NAPD Director Clive Byrne said: "This survey provides valuable insight into the ever-changing attitudes and prevalence of cyberbullying among post-primary pupils.
"The findings are quite disturbing because despite ongoing media attention around the problem, there has been a 33% increase in students reporting to being victims of cyberbullying compared to last year.
"Furthermore, there is an 80% increase in students admitting to being the transgressors of cyberbullying. For educators, parents, students and school leaders this reality poses a clear and present threat to the collective morale of schools across the country."
The NAPD is set to make a formal submission on cyberbullying to the Department of Communication, Energy and Natural Resources' Internet Content Advisory Group. Among a series of recommendations the association will call for a national cyberbullying policy.
Mr Byrne added: "Cyberbullying is not just restricted to the school playground, it follows victims home through the medium of their phones or on the web.
"Hateful and insulting content remains as permanently etched on the psyche of victims as it does on the web.
"Failure to adequately address this issue does a disservice to the young people that both educators and parents are obliged to protect from harm."