Waitrose has become the latest supermarket to remove beefburgers from its shelves as a result of the horsemeat scare.
The company said it had taken frozen burgers made by Dalepak, one of the firms at the centre of the horsemeat contamination investigation, off sale "as a precaution" when it had its accreditation suspended.
Ten million burgers have been taken off supermarket shelves across Ireland (OTC BB: IRLD - news) and the UK as a result of the scandal when it was revealed some lines sold by Tesco (Other OTC: TSCDY - news) , Aldi, Lidl and Iceland were discovered to have contained traces of horsemeat.
In a statement, Waitrose said its burgers had since been tested and were found to be 100% beef.
"As a consequence we are 100% confident in the integrity of our supply chain," it said.
"The ingredients in our burgers are simple with all meat traceable back to British farms that we know.
"Our technical team visited the Dalepak site last week and were happy that our products were produced to our high specification and separately from other companies' products (ours are produced at 6am before other any other burgers)."
The ABP Food Group, one of Europe's biggest suppliers and processors, stopped work at its Silvercrest Foods plant in County Monaghan, Ireland, after tests last week revealed contamination in frozen burgers.
Tests had already shown that Silvercrest Foods and another of the company's subsidiaries, Dalepak Hambleton in Yorkshire, supplied beefburgers with traces of equine DNA to supermarkets, including one product classed as 29% horse.
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