Dumped turkey waste, offcuts and a telltale label provided the evidence that allowed investigators to link the outbreak of bird flu at the Bernard Matthews farm in Suffolk and the company's business in Hungary, The Independent on Sunday has learnt.

The revelations come as the Environment minister Ben Bradshaw said the company could face prosecution for a "biosecurity breach" at the plant in the village of Holton.

Investigators believe that the virus got into turkey sheds at the farm from offcuts and waste from the imported meat, which was processed at the site. They add that a label found at the plant suggests that the company was "economical with the truth" about how close its Hungarian operations were to an eruption of the disease in the country last month.

The company denies this, saying it "always fully co-operated with the investigation" and that it "had never not given them all the information they have asked for".

The two discoveries have led ministers to abandon their earlier conviction that the virus was brought to the farm by wild birds, and underlined an international reappraisal of the role of factory farming and the poultry trade in the worldwide spread of the disease.

Source: The Independant