GARDAI have spoken to two schoolgirls as part of their investigation into the death of 13-year-old Erin Gallagher, who took her own life after being bullied.
The teenage girls were informally interviewed amid concerns over the safety of a number of others, the Irish Independent has learned.
It is understood the girls went voluntarily to a Co Donegal garda station along with their parents.
The development comes as gardai also examine text messages sent to Erin's phone.
The teenager died at her home in Ballybofey, Co Donegal, on Saturday.
It is understood gardai are concerned for the safety of a number of teenagers as a result of her death.
Vitriolic comments have been posted online about those alleged to have been involved in bullying the schoolgirl.
"There is a real concern for their safety," said one source.
"At the end of the day all those involved in this tragic incident are very young people. The facts of the case will be required for an inquest but there is also a welfare aspect to this."
HSE suicide prevention experts and social workers are involved in discussions around the case. It is understood there are fears of both attacks on the children concerned as well as possible copycat suicides.
"There is a great deal of anger out there and there is always the possibility that some misguided individuals may try to take the law into their own hands," said one source.
"But there is also a real concern for the mental wellbeing of young people who are themselves just children."
The Finn Valley College pupil will be laid to rest today after 11am Mass at St Mary's Church in Stranorlar.
The revelations come as a new survey finds victims of cyber-bullying may have no one to turn to in school to help them deal with the problem.
Education cuts mean that schools cannot offer the same one-to-one counselling service to students in distress, according to a new survey by the second-level school management organisation, the Joint Managerial Body (JMB).
Career guidance teachers are trained to act as counsellors to vulnerable pupils and the need for one-to-one interventions is regarded as critical.
A guidance counsellor could devote many hours to guiding individual pupils through difficult periods and helping them to avoid a crisis. But guidance and counselling services now have to be provided out of a school's general allocation of teaching hours, which has led to massive disruption.
Erin's mother Lorraine Gallagher has said gardai took her daughter's mobile phone as part of the investigation. She believes her daughter may have received a bullying text before she took her own life.
Gardai are also examining comments left on Erin's page on the ask.fm website. Posts on the site are left anonymously.
Gardai are refusing to comment, and a spokesman said: "Investigations into the incident are ongoing."
Erin's friends have organised a walk through the twin towns of Stranorlar, where Erin went to school, and Ballybofey, where she lived. It's expected to take place next Monday evening, on what would have been Erin's 14th birthday.
The Irish Society for the Prevention of Cruelty to Children (ISPCC) has urged parents to speak to their children about cyber-bullying.
Tess Noonan, ISPCC manager, warned: "Cyber-bullying is a 24-hour insidious issue. Children who are exposed to this form of bullying can face a 24-hour barrage of insults, threats and innuendo which can mean that there is no let-up from the abuse.
"The ISPCC is asking every parent to speak to their child today about their experiences online and make this a regular part of conversation at home."