A West Yorkshire slaughterhouse and a meat plant in Wales have been raided by police and food safety officials.
The raids are the latest development in the ongoing investigation into the mislabelling of meat products.
In a statement, the Food Standards Agency said agency officials and the police entered Peter Boddy Licensed Slaughterhouse, Todmorden, West Yorkshire which it believed had supplied horse carcasses to Farmbox Meats Ltd, Llandre, Aberystwyth.
The agency and the police are looking into the circumstances through which meat products, purporting to be beef for kebabs and burgers, were sold when they were in fact horsemeat.
The FSA has suspended operations at both the plants.
The agency has detained all meat found and seized paperwork, including customer lists from the two companies.
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