An outbreak of bird flu has been confirmed at a turkey farm in eastern England although the exact strain is not yet known, Britain's farm ministry said.
The ministry said preliminary results from the farm on the border of Norfolk and Suffolk were positive for the H5 strain but it is not known if it is the deadly H5N1 variety which has swept across Asia, Europe and Africa.
All birds at the farm, which also houses ducks and geese, will be culled and protection and surveillance zones are being set up, the Department of Environment, Food and Rural Affairs (DEFRA) said in a statement.
"Full confirmation of results, including whether or not this is H5N1 and whether the strain is high or low pathogenic will follow," the ministry added.
Britain had an outbreak of the H5N1 strain in February at a turkey farm in Suffolk, eastern England.
The virus has killed more than 200 people worldwide since 2003, most of them in Asia, and millions of birds either died from it or been killed to prevent its spread.