The farm prepared birds for the Christmas market

The virus was first discovered on 11 November at Redgrave Park Farm near Diss on the Norfolk-Suffolk border.

Defra said the disease had now been confirmed at the nearby Hill Meadow Farm, Knettishall.

The new infected premises is operated by the same company as the site of the first outbreak, and all 9,000 turkeys had already been culled.

Hill Meadow Farm outside a 3km protection zone which had originally been set up around Redgrave Park Farm, but inside a wider restricted area covering Suffolk and parts of Norfolk.

Locations of H5N1 outbreaks and precautionary culls. Enlarge Map

A new 3km protection zone around the fresh case has been established, and a wider surveillance zone covering both sites has also been imposed.

In total, more than 28,000 birds were slaughtered following the suspected outbreak of H5N1, a variant of the disease capable of being transmitted to humans.

The cull of poultry on four sites suspected of being infected ended on 18 November.

A 3km protection zone and a 10km surveillance zone have been set up and the farm is co-operating with vets.

Defra are still waiting for the results of culls at two farms in Norfolk - Stone House, West Harling, and Bridge Farm, Pulham.

Fred Landeg, the acting chief veterinary officer, said the latest results highlight the importance of vigilance from poultry farmers.

He added: "It is essential they practice the highest levels of biosecurity and report any suspicions of disease to their local Animal Health office."

A national and a local disease control centre have been established in Bury St Edmunds, with text messages sent to all bird keepers nationwide - especially those in zones on the poultry register.

The cost of animal infections is thought to have cost the government and taxpayer more than �120m this year.

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