By Ben Spencer and Mario Ledwith PUBLISHED: 20:45 EST, 24 January 2013 | UPDATED: 13:22 EST, 25 January 2013 Tesco has apologised after one its stores continued to sell a line of burgers that should have been withdrawn in the wake of the horse meat scandal. Customers were alarmed when the own-brand 'Free From' quarter pounder prompted an alert at the checkout, informing them that the 'product has been withdrawn from sale'. But despite the warning, staff at the store in Cowley, Oxfordshire, ignored the system and allowed the customers to purchase the burgers anyway. Apology: Tesco apologised after customers purchased a variety of burger that should have been withdrawn in the wake of the horse meat scandal at its store in Cowley, Oxfordshire
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Tesco customers purchased withdrawn line at store in Cowley, Oxfordshire
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Staff sold burgers despite a checkout alert warning they were 'withdrawn'
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Waitrose pulled six product lines after supplier Dalepak lost accreditation
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Dalepak one of three meat processing firms found to contain horse DNA
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Waitrose '100 per cent confident' that there was no horse meat in burgers
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Managing director aid horse meat scandal was inevitable due to major supermarkets squeezing suppliers
Tests: @placeholder said all burgers had been tested and come back negative for horse DNA
Although @placeholder's withdrawal came to light yesterday, the products were removed from stores on Monday.