Ananova:

Test results on dead turkeys taken from a farm close to the initial centre of the Suffolk bird flu outbreak are due in, as a wider cull of thousands of animals continues.

Turkeys at Grove Farm, near Botesdale, were being slaughtered on suspicion of having the disease after dozens of birds were found dead.

Positive tests will show the deadly H5N1 virus had spread from the original source at Redgrave Park Farm, which was discovered on Sunday.

Animals at three neighbouring farms were also being killed in a precautionary cull.

The three farms are outside the 10km (six-mile) surveillance zone but within the restricted zone which covers Suffolk and most of Norfolk. In all, nearly 30,000 birds will have been gassed by the end of the day.

The same staff work at all five sites, which are owned by Redgrave Poultry, and Defra feared they might have accidentally passed on the virus.

They are Stone House Farm in West Harling, Norfolk; Bridge Farm in Pulham, Norfolk; and Hill Meadow in Knettishall, Suffolk.

Chris Kaufman, Unite's national officer for food and agriculture, said the most pressing concern was to isolate and then contain the outbreak.

"The authorities learnt a great deal from the Bernard Matthews outbreak so should swing into action like a well-oiled machine to try to limit the effects of this latest outbreak."

A Defra spokeswoman said about 30 birds at Grove Farm had been discovered dead by veterinary officials, prompting the cull to be reclassified as a "slaughter on suspicion" of disease.