The Food Safety Authority detected the horse DNA during a survey of beef products sold by retailers, including Aldi, Lidl, Tesco, Dunnes and Iceland.

The issue has raised serious concerns about traceability in Irish Food - an investigation into the source of the horse meat is continuing.

One of the supermarkets involved, Tesco, says it does not know how many burgers containing horse meat have been sold.

The supermarket is one of five retailers in which burgers containing horse meat has been detected after an investigation by the Food Safety Authority.

The issue has raised serious concerns about traceability in Irish Food. An investigation into the source of the horse meat is continuing.

In the case of one of the Tesco products - almost 30% horse meat was found.

Chief Executive of Bord Bia Aidan Cotter has said it's too early to say what effect the discovery will have on Irish exports - but we need to get to the bottom of what happened as soon as possible:

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