Three men have been arrested at meat plants inspected by the Food Standards Agency, Dyfed-Powys Police said.
Two men have been arrested at Farmhouse Meats near Aberystywth, west Wales and another man has been arrested at the Peter Boddy Slaughterhouse in Todmorden, West Yorkshire.
All three have been arrested on suspicion of fraud, and are being interviewed by police and FSA staff.
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