Horse meat, horse DNA, and pig DNA has been discovered in burgers and other ground beef products, according to Ireland's Agriculture Minister Simon Coveney.

Coveney, an Irish food safety watchdog, announced that one burger, sold by global retailer Tesco, was made of roughly 30 percent horse meat. The Agriculture Minister blamed the lone meat processor in County Monaghan, on the border with Northern Ireland, for the horse meat find, which he called "totally unacceptable."

Coveney told state broadcaster RTE that an imported additive used to make the burger appears to have been packed with horse meat.

Coveney said the additive was "either falsely labeled, or somebody made a mistake, or somebody was behaving recklessly. That allowed some horse meat product to come into the system that shouldn't have been here."

He added, "A mistake has been made here, it has been flagged by our systems as it should have been, and we will take the appropriate action to ensure it doesn't happen again."

U.K.-based Tesco PLC has issued an apology, saying that it was pulling Tesco-brand burgers from stores in Britain and Ireland as a precaution. Horse meat poses no health risk to consumers, but culturally it is not eaten in the UK and Ireland.

“We immediately withdrew from sale all products from the supplier in question,"  Tesco's Group Technical Director Tim Smith said in a statement.

"We are working with the authorities in Ireland and the UK, and with the supplier concerned, to urgently understand how this has happened and how to ensure it does not happen again. We will not take any products from this site until the conclusion and satisfactory resolution of an investigation.”

In related news, the Food Safety Authority of Ireland issued a statement on Tuesday saying it had found traces of pig DNA in 85 percent of the burger products it tested in Irish supermarkets, including those operated by British frozen food specialist Iceland, German discounters Lidl and Aldi, and supermarket giant Spar. Irish stores, including Dunnes — the country's largest domestically owned supermarket chain — also carried beef with horse or pig DNA.

Alan Reilly, chief executive of the FSAI, said there was no health risk but also no reasonable explanation for horse meat to be found.

"The products we have identified as containing horse DNA and/or pig DNA do not pose any food safety risk and consumers should not be worried," he said.

The FSAI said consumers can return implicated products to retailers.