Irish authorities are sure that "filler product" found in contaminated burgers sold in supermarkets came from Poland and was a mixture of beef and horse offcuts, the Food Standards Agency (FSA) has said.
The contaminated meat was in the form of blocks of frozen product from a Polish supplier that had been used for a year, FSA chief executive Catherine Brown told the Commons Environment Committee.
Investigations are going on into how long contaminated meat might have been in use, Ms Brown told MPs.
