Horse Meat Found in Ireland, U.K. Burgers

What are they putting in the glue then?

A disturbing discovery has led some consumers to wonder "Where's the beef?" in their supermarket burgers. The Food Safety Authority of Ireland said it had discovered horse and pig DNA in burgers sold by grocery stores in Ireland and the United Kingdom, according to reports.

The finding includes a burger sold by global supermarket chain Tesco that contained 29% horse meat, according to the Associated Press.

U.K.-based Tesco -- one of the world's largest food retailers and known in the U.S. under its Fresh & Easy brand -- apologized for the horse meat-laden burger and pulled store brand burgers from groceries in Britain and Ireland, according to AP.