Farmers in the Scottish Borders say they are concerned after traces of horse and pig meat were found in beef burgers.
The Irish Food Safety Authority tested 27 beef burgers, from 5 British supermarkets, including Tesco and Iceland.
10 burgers tested positive for horse DNA, and 23 tested positive for pig DNA.
The products were tested at 2 factories in the Irish Republic, and 1 in North Yorkshire.
One processing company says its suppliers in Europe may be responsible.
Farmers fear the situation could have a knock on effect.
Robert Neill farms at Upper Nisbet Farm near Jedburgh. He said: "We have to trust everybody throughout the whole process of supplying meat.
Farmers are just the start of the process, but unfortunately if something like this happens, we take the brunt of the knock on effect, whether it be production, consumers not eating, prices go down, so yes it is a worrying scenario at the moment."
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