A Belfast man is thought to be responsible for posting online images of a teenage girl performing an intimate sex act at a Co Meath concert which has erupted into an internet bullying row.
The graphic images taken at the Eminem's Slane Castle gig on Saturday have gone viral, leading to a torrent of abusive comments about the girl.
Sources said she was so distraught she had to be sedated in hospital yesterday afternoon.
Gardai have still not received a formal complaint about the photos. The man who posted the images is believed to be from the Clonard area of west Belfast. However, it's emerged the girl has made a separate complaint of sexual assault at an event that does not relate to the online photos. One source said: "The primary concern for gardai is for this vulnerable teenager and her state of mind.
"Gardai have been dealing with her and her family. This is a very sensitive case.
"The teenager has not been medically fit enough to make a formal statement yet but when that happens this could turn into a sexual assault investigation."
It is understood the girl's parents were notified by gardai on Saturday that their daughter had made a complaint of being assaulted at the concert.
The teenager was treated in hospital before being allowed to return home.
However, images of her performing a sex act then went viral on the internet and she was readmitted to hospital where she was undergoing tests last night.
A Garda spokesman told the Belfast Telegraph: "We are aware an image exists and are investigating the full circumstances."
A PSNI spokeswoman said it had not been contacted by the Republic's police force. Abusive comments directed at the teenager have caused outrage.
Former Armagh GAA captain Jarlath Burns tweeted: "As child protection teacher in school of 1,500 I can attest to the devastation that girl in Slane must be feeling. Please delete tweets.
"She needs supported not judged."
Meanwhile, Kellie Turtle of the Belfast Feminist Network said the online reaction was "disturbing".
She said: "Even though some young people have lost their lives as a result, thousands of others still fail to see the harm."
A Facebook group set up in support of the teenager had more than 1,600 members last night.