About 55,000 birds are to be culled after a new case of bird flu was detected on a farm in Suffolk.
The Department for Environment, Food and Rural Affairs (Defra) said the H5N8 strain of avian flu has been found at Grange Farm in Redgrave.
Public Health England said the risk to public health from the virus is very low.
Gressingham Foods confirmed the birds will be culled, even though none of them currently has avian flu.
The strain was detected in the environment, rather than the birds.
The discovery follows investigations after avian flu was discovered on a separate poultry farm near Redgrave last month.
The premises will be cleansed and disinfected to reduce the risk of further spread, Defra said.
A 3km protection zone and 10km surveillance zone are already in place following the previous case.
The Food Standards Agency said bird flu does not pose a food safety risk for UK consumers.