The students voluntarily presented themselves to gardaí in Donegal in the company of their parents amid claims the 13-year-old had been bullied both at school and online.
The Finn Valley College pupil was found dead at her family home in Ballybofey, Co Donegal. She is understood to have been babysitting her 4-year-old brother, who was close by.
Gardaí have seized Erin’s mobile phone, which her mother Lorraine claims has messages of a bullying nature on it.
Erin had also posted messages on social network site ask.fm, in which she blamed those she claimed were responsible for the bullying.
Gardaí are remaining tight-lipped about the latest development, only confirming that investigations are “ongoing”.
Erin’s mother has revealed her daughter tried to take her own life some weeks ago but “seemed to be doing fine” in recent weeks.
She had attended a psychologist as recently as two weeks ago.
Ms Gallagher confirmed her daughter’s bullying had worsened since she returned to school after the summer holidays.
“She was being bullied on Facebook, at school, everywhere,” said Ms Gallagher.
Erin’s circle of friends are still coming to terms with the loss of their friend. Her funeral takes place at 11am at St Mary’s Church in Stranorlar today.
R.I.P to Erin Gallagher this is what happens when people bully in ends in tragedy They should be named and shamed regardless of their ages!— Ciara💞 (@CiaraMurphyx) October 30, 2012
A tribute Facebook page has attracted more than 7,500 friends and supporters since it was set up on Saturday night.
Thousands of people are also expected to attend a walk in memory of Erin and against bullying.
The Erin Gallagher Memorial Walk has been arranged by her friends for Nov 8 — the day on which Erin would have celebrated her 14th birthday.
The mayor of Donegal, Frank McBrearty, has called for legislation to be enacted to deal with the issue of cyberbullying in the wake of this and other recent suicides.
However, the Association of Secondary Teachers Ireland has insisted teachers are doing all they can to tackle cyberbullying — despite the issue being almost impossible to fully stamp out.
The union’s assistant general secretary, Moira Leydon, said schools have had policies specifically targeting bullying for more than 20 years.
However, she said the development of technology in recent years has made blocking out all forms of bullying far more difficult as the issue evolves.
“In the case of cyberbullying, I think it’s important that we would distinguish the fact that bullying is always a behavioural issue; but technology has made it more insidious, more invasive, more targeted,” said Ms Leydon.
“Bullying as a behaviour is a phenomenon that our society as a whole has to come to terms with.”
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