UK supermarket giant Tesco has found itself at the centre of an investigation conducted by Sky News, which uncovered evidence of criminal activity in the store's pig meat supply chain.

Thousands of animals slaughtered and unwittingly sold to Tesco's consumers were found to have been fed on meat scraps, salami sausage and takeaway restaurant waste in pigswill. Bred by the Wiltshire farming company WE & DT Cave Ltd, the pigs were then sold on illegally to Tesco accompanied by false paperwork.

The criminal scam contravened Tesco's own safety standards and customer assurances. The company stressed that it seeks to offer full traceability for all food products and banned the use of pigswill by suppliers because of the lack of control over its ingredients.

Two years ago, the government warned that feeding pigs to pigs could result in a brain disease epidemic similar to that of BSE in cattle. Interestingly however, Sky News also linked Cave to senior labour peer and Government Chief Whip Lord Carter, a major shareholder who apparently lent the farm around £100,000.

In response to the investigation, Tesco produced a statement saying that "falsified animal movement records will be more readily detectable" now it has tightened its checks.

Meanwhile Lord Carter issued a statement to the effect that he has no involvement in the operation of the company.