A Labour TD has said protected disclosures by two garda whistleblowers, who allege a number of unlawful deaths were not investigated as homicides, are a "profound and serious issue".

Speaking on RTÉ's Today with Sean O' Rourke, Alan Kelly said he has been aware of the issue for some time and described the two members of the force as "very brave people" who have come forward and "put this information out there".

"Unfortunately there have been deaths in this country which have not been classified correctly and where people have died of something akin to homicide and it has been classified as a road traffic death, misadventure, assault or a number of other things, and it is quite astonishing, it is absolutely astonishing and incredible that this has happened," he said.

Mr Kelly said the two whistleblowers have made attempts over 15 months to get this information dealt with and have not been able to and have "been stopped and blocked".

Yesterday, the Policing Authority said it is still not satisfied with the assurances given by gardaí in relation to the recording and classification of 41 homicide incidents between 2013-2015.

The body is to question An Garda Síochána about its continuing failure to publish a review into homicide figures at a public meeting this month.

The review was originally due to be made available to the Policing Authority in June last year but has yet to be published.

Mr Kelly said this is not a victimless issue, adding that it is about peoples' lives and public confidence.

He also said it is not something that management in An Garda Síochána can say has gone on in the past and has stopped. "It goes right up to the very day," he said.

Mr Kelly said he wants to know why the Garda Commissioner has not done a Section 41 on this.

A 'Section 41' occurs where an issue is so serious in relation to garda activities that the Garda Commissioner notifies the minister.

He also said the Minister for Justice needs to come out and publicly make a statement on this issue.

Minister for Justice Charlie Flanagan said that he was "extremely concerned" about the reports.

In a statement, he said that he has not received any protected disclosures or allegations that unlawful killings were not investigated.

The Minister said that garda management are "adamant that all unlawful killings are investigated" and that he has seen no evidence to the contrary.

Mr Flanagan said that he has asked gardaí for "formal assurances in this regard."

He also said an issue in relation to the classification of garda figures had been identified some time ago and that the gardaí, the Policing Authority, the CSO and the Department of Justice were working to resolve it.

The Policing Authority has expressed its concern over the issue and garda management is due to appear before it in public later this month.