The Times claims that Gressingham Foods, which is supplied by the affected farm, received regular supplies of ducklings delivered by a Dutch exporter.
The focus of inquiries is on the vehicle and driver, whether there are any links with previous outbreaks of the virus in mainland Europe and whether there was any opportunity for the disease to be spread through the Gressingham company via vehicles, equipment or staff.
Imports of speciality poultry meats by Gressingham Foods are also part of the official inquiry, which is also looking at wild birds. This meat is frequently processed or packed at the company’s plant less than 750 yards from Redgrave Park Farm, near Diss, which is at the centre of the alert.
However, the company has hit back claiming no link with the Netherlands.
Redgrave Park Farm operations manager Geoffrey Buchanan said: “We know of no direct link with the Netherlands and the five farms involved. All of our turkey poults and the feed are from the UK.
“The geese and ducks at Redgrave Park farm were also from the UK.”