Horse DNA has been found in some beef burgers produced at a factory in Northallerton. Traces of horse meat were discovered during testing by The Republic of Ireland's Food Safety Authority.
The burgers were produced at the Dalepak Hambleton plant, and two other factories in Ireland.
Tesco, Lidl, Aldi, Iceland and Dunnes Stores say they are removing the products from their shelves immediately.
The Irish Food Safety Authority says the meat poses no health risk but raises concerns about food traceability.