Birds Eye says an Irish processor supplied the meat used in two of its products which were found to have horse DNA in them.
The company withdrew its Spaghetti Bolognase and its Beef Lasagne from the shelves last month following the discovery of horse meat.
The products were supplied to Birds Eye by the Belgian company Frigilunch N.V. - which in turn, was supplied by the Irish company QK Meats, based in Co Kildare.
In a statement, Birds Eye says the findings have been reported to the Food Safety Authority of Ireland - and the Belgian company has suspended QK Meats as a supplier.
No other Birds Eye products have tested positive for horse DNA.