Britain has called for DNA testing of processed meat across the European Union, as EU agriculture ministers met in Brussels to discuss the scandal of beef adulterated with horse meat.
Arriving for the emergency summit, Environment Secretary Owen Paterson hinted that investigations by UK food safety authorities may lead to further raids, following action at an abattoir in West Yorkshire and a Welsh processing plant on Tuesday.
Prime Minister David Cameron told the House of Commons that anyone involved in passing off horse meat as beef should face "the full intervention of the law", but insisted there was no evidence that products on the shelves of British shops were unsafe to eat.
Mr Paterson said that the raids, on the Peter Boddy slaughterhouse in Todmorden and meat processing plant Farmbox Meats at Llandre in Aberystwyth, followed methodical work by the Food Standards Agency, tracing back through the paperwork of companies where horse meat may be involved.
And he added: "There may be more procedures coming forward but I don't want to prejudice those investigations in public."
The two plants were temporarily shut down amid claims they supplied and used horse carcasses in burgers and kebabs.
FSA director of operations Andrew Rhodes said its probe had revealed "blatant misleading of consumers" and investigations would continue "until there is nothing left to find".
But solicitor Aled Owen, representing Farmbox, said the processing firm was co-operating with FSA inquiries and denied any wrong-doing. The company had a legitimate business cutting horse meat for delivery to Belgium, and wished to express its "dissatisfaction" with "untrue" statements by the FSA, he said.
Ahead of his meeting with counterparts from France, Ireland, Romania, the Netherlands and Luxembourg, Mr Paterson said it was now clear that meat contamination was a Europe-wide problem.
No-one had "a clue" until recently that beef products had been adulterated, said the Environment Secretary, adding that it had initially appeared to involve "very small amounts" of horse meat.
