The European Commission confirmed on Saturday that the avian flu which killed 2,600 turkeys at a Suffolk farm in eastern England was the H5N1 virus.
The EU executive said in a statement that the European Union's reference laboratory in England had confirmed the deaths were caused by the deadly strain, which can be transmitted to humans.
"Further tests to characterise the virus are underway in order to ascertain whether or not it is the Asian strain," said the statement.
According to the Department of Environment, Food and Rural Affairs, 159,000 other turkeys which were on the farm would be slaughtered.
A three-km protection zone and 10-km surveillance zone has been set up around the farm, while strict movement controls have been in place and farmers been told to keep poultry indoors.
Officials announced on Friday that they had detected the virus at a farm run by food processing company Bernard Matthews at Holton, Suffolk. Government vets were called to the farm late Thursday night.
In May last year, more than 50,000 chickens were culled after an outbreak of the H7 bird flu at farms in the neighboring county of Norfolk.
In March 2006, a wild swan found dead in Scotland was confirmed having the H5N1 strain of the virus.
The H5N1 strain can be transmitted to humans and has killed more than 160 people worldwide since 2003. Most of the victims were in Asia.