Tesco has admitted an own-label spaghetti bolognese in the UK contained horse DNA.

The UK’s largest retailer announced this evening the product, sold under its cut-price Everyday Value own label, contained over 60% horse DNA in some tests.

Tesco, which has pulled a number of products in the last month containing horse meat, said it had withdrawn the frozen spaghetti bolognese from sale last week. The product was made at French firm Comigel, the company that supplied the Findus frozen lasagnes on sale in the UK that were last week found to have up to 100% horse meat.

Tim Smith, Tesco’s technical director, said the retailer’s tests had identified the bolognese contained horse DNA. “Of the positive results, most are at a trace level of less than 1% but three showed significant levels of horse DNA, exceeding 60%,” he said.

Smith said Tesco would no longer buy product from the Comigel plant. “The frozen Everyday Value spaghetti bolognese should contain only Irish beef from our approved suppliers. The source of the horsemeat is still under investigation by the relevant authorities. The level of contamination suggests that Comigel was not following the appropriate production process for our Tesco product and we will not take food from their facility again.”

The saga began last month when it emerged frozen burgers on sale at retailers including Tesco, Aldi and The Co-operative Group contained horse meat.

A Tesco beef burger contained 27% horse DNA. The burgers were made by plants in the UK and Ireland owned by Irish processor ABP Food Group. There has been, as yet, no confirmation of the source of the horse meat. Officials in Poland, which was first under suspicion, has insisted it is not to blame.

The affair was heightened last week when Findus admitted lasagne on sale in the UK contained horse meat. There were further recalls in the UK, France and Sweden of Findus and Comigel products. A German retailer has also pulled lasagne lines.

At the weekend, France alleged Romania was the source of the horse meat contained in the Findus and Comigel products.

Initial investigations by the French government linked the contamination to an unnamed company in Romania, via traders in Cyprus and the Netherlands, a meat processor in France and Comigel to frozen food giant Findus.

However, Romania this afternoon hit back at claims by the French government that two slaughterhouses in the eastern European country knowingly sold horse meat as beef, marking another twist in the contamination scandal.