Gardaí have begun a probe into how information in relation to the investigation of a former minister for alleged child abuse became public.

A chief superintendent has been appointed to carry out this investigation.

Garda Headquarters confirmed that all the circumstances surrounding the disclosure of information in relation to an ongoing criminal investigation are being examined.

Former Fianna Fáil Minister Pat Carey issued a statement last night absolutely and unconditionally denying any alleged impropriety.

He also said he did not know if allegations of abuse published in the media related to him but said he was distraught to learn of such allegations in a national newspaper.

Gardaí say this is not just an internal investigation. It is believed that all other potential sources including officials from the Department of Justice, legal representatives and alleged victims may have to be looked at as part of the investigation.

The Minister for Justice Frances Fitzgerald said she's concerned about the way that information in relation to the investigation was leaked.

Speaking to reporters in Dublin, Ms Fitzgerald said she did not wish to comment on any particular case because, she said, operational matters were “fully the remit of the Garda Síochána and the Commissioner”.

But she said she believed the Commissioner would be concerned “about any inappropriate behaviour in terms of any garda investigation”.

A statement from the Department of Justice earlier today said: "In view of reports that officials of the Department of Justice may be among those who have to be looked at as potential sources as part of an examination by An Garda Síochána into the disclosure of information relating to an investigation into alleged child abuse, the Department wishes to make it clear that it had received no information on the investigation in question prior to its disclosure to the media."

This is the third such investigation into the disclosure of information that has appeared in the media that has been ordered by the Garda Commissioner Noirín O'Sullivan.

One relates to the case of the protesters including Deputy Paul Murphy who are currently before the courts in relation to the protest last year during when the Tánaiste attended a graduation ceremony in Jobstown.

The other investigation resulted in the arrest and questioning of a senior garda officer.

Fianna Fáil has confirmed the decision of Mr Carey to step aside from his role as the party's Director of Elections for the forthcoming general election.

In a statement last night, Mr Carey said he was also concerned at comments allegedly attributed to gardaí in media articles in the past 24 hours.

In order to allow the good work of the organisations that he is involved in continue without controversy, he said he has decided to step aside from his various roles including his positions as chair of the Red Cross and Director of Elections for Fianna Fáil.

In a statement last night, a spokesperson for the party said they had received confirmation of his decision to step aside from this role and as a member of Fianna Fáil.

It noted the statement Mr Carey had made through his solicitor.

The Irish Red Cross has also issued a statement after Mr Carey stood down from his role as Chairperson of the organisation.

The statement, issued to RTÉ News, says: "Irish Red Cross has been informed by its Chairperson Mr Pat Carey of his decision to step down from all public positions due to serious allegations being reported in the media.

"Irish Red Cross respects Mr Carey's decision to step down and the authorities must now be given time to investigate."

Mr Carey took up his voluntary position as Chairperson this May.The organisation said its work at home and abroad is not affected.

Meanwhile, a former Fianna Fáil party adviser has described the reporting of alleged abuse by a former Government minister as a "red flag moment".

Speaking on RTÉ's Today with Keelin Shanley, Paddy Duffy said the incident raises serious questions about how these cases are brought into the public domain.

In relation to Mr Carey standing down as Fianna Fáil's director of elections, he said he believes that acting on the precautionary principle was absolutely the right thing to do to try to prevent any collateral damage to any of the political bodies of which he is a member.

Mr Duffy said there were matters of public and private importance; that of the victims rights and that of the right of every citizen to good name, character and due process.

"It does raise serious questions about how these cases are brought into the public domain and what the rights of individuals are.

"My own feeling is that this is not the way that legal affairs should be conducted," he said.