An Irish army poster girl has reported being sexually assaulted by another soldier, it has emerged.

The allegation is one of the reasons Ulster woman Lieutenant Collette McBarron doesn’t want to return to the barracks where the assault is claimed to have occurred, friends disclosed.

The army had ordered Lt McBarron (23) back to Aiken Barracks, Dundalk, after a stint in Dublin.

But now it has been revealed that the beautiful young officer from Donegal had reported being sexually assaulted by a fellow soldier in the Dundalk installation.

The Irish Defence Forces confirmed that a full military investigation had been carried out into the former Miss Ireland contestant’s allegation.

The Irish army said it had not proceeded with the case for lack of evidence.

Friends insist Ms McBarron, originally from from Donegal Town, is committed to a career in the Republic’s defence forces, but is distraught at having to return to Aiken Barracks.

The officer, who was linked romantically to Olympic boxing hero Kenny Egan, was transferred to Dublin’s Cathal Brugha barracks for the duration of the army investigation.

She has now been transferred back to the location where she alleged the offence occurred.

Collette’s sister Christina said she is distraught because the barracks bring back bad memories for her.

“She can't believe she's being sent back there. It's just the fact of all the memories that she has there,” Christina said. “Even though the case was dismissed, they still felt it necessary for her to be moved.”

However, Christina is confident her sister will get through this trauma saying: “She's braving it up, she's a strong girl.”

It emerged earlier this week that the model feared the move was instigated after she was snapped socialising in some of Dublin’s top nightspots.

But an Irish army spokesman said her return to Dundalk was purely because the investigation into the sexual assault had finished.

He said: “Second Lieutenant Collette McBarron was temporarily attached to the 2nd Infantry Battalion, Cathal Brugha Barracks, Rathmines from February 2008 while an investigation of sexual assault was investigated.

“She made an allegation of sexual assault against a fellow officer in Dundalk at the time, and in the interest of fairness was moved to Dublin while this was being investigated.

“A full Military Police investigation, led by a senior officer, was carried out; however charges were dismissed due to a lack of evidence. These investigations have been completed for a number of months and 2/Lt McBarron has now been returned to her parent unit.”

The spokesperson said it was appropriate for Ms Barron to return because the officer whom she made the claims about has been moved from Dundalk.

“The (soldier) against whom the allegations were made is still serving in the Defence Forces, but does not serve in Aiken Barracks,” he added.

Friends said the young lieutenant is apprehensive about returning to the scene of the alleged assault.

“Collette would love to give her side of the story about the transfer but as a serving officer it is prohibited to speak to the media.

“She's not allowed to say anything. She wants to tell everyone her side of the story but she can't,” Christina added.

The female soldier was court-martialled for going absent without leave in September 2007.

She was fined €950 for dereliction of duty after admitting to wrongly leaving her base while on security duty.