Irish authorities believe that "filler product" found in contaminated burgers came from Poland and was a mixture of beef and horse offcuts, the Food Standards Agency (FSA) has said.
The contaminated beef, which was sold in supermarkets, was in the form of blocks of frozen product from a Polish supplier that had been used for a year.
Investigations are going on into how long contaminated meat might have been in use, FSA chief executive Catherine Brown told the Commons Environment Committee.
More top news
Temperatures not sliding far - around 20C at midnight in places, so another restless nights sleep as it stays uncomfortable and stuffy.
With lines catapulting right and centre in the complex investigation over Trump's links with Russia, this is how the story unfolded.
An incredible £5m has been raised in support of the survivors and families of victims injured or killed in the Manchester bomb attack.