German authorities have confirmed a second case of the H5N8 strain of bird flu in the eastern state of Mecklenburg-Vorpommern, with the virus found in a wild bird.
The strain is highly contagious among birds but has never been detected in humans.
In a statement agriculture minister Christian Schmidt said: "For the first time, the H5N8 virus has been confirmed in a wild bird in Mecklenburg-Vorpommern.
"With that the suspicion is strengthened that wild birds are connected with the cases in Mecklenburg-Vorpommern as well as in the Netherlands and Britain."
Bird flu has been found at a second farm in the Netherlands, according to Dutch authorities. 43,000 chickens are to be destroyed, they told Reuters.
The cull of 6,000 birds at a farm in east Yorkshire began this afternoon following an outbreak of bird flu.
A team of experts put the animals into crates before locking them in an airtight container where they were gassed. Their bodies will later be incinerated.
The cull will continue in the morning but it will be a few days before experts will know if it has been successful in stopping the spread of the disease.
The H5N8 bird flu strain found in ducks at a breeding farm in East Yorkshire is the same as the one identified in the Netherlands and Germany, the Department for Environment, Food and Rural Affairs confirmed today.
Assurances that the current bird flu outbreak will not affect the supply of turkeys for Christmas dinners around the country have been made today by UK farming experts.
Andrew Large, chief executive of the British Poultry Council, said: "The current outbreak has a 10km restriction zone and this will have no impact on the supply of turkeys for the festive period."
The poultry adviser for the National Farmers' Union, Gary Ford, added: "Farmers are working extremely hard at this time of year to prepare for the Christmas market and consumers can be reassured that buying British poultry (chickens, turkeys, ducks) is safe."
Discount supermarket Aldi has said it expects to see egg shortages in its stores following the bird flu outbreak in the Netherlands.
The supermarket chain, which has over 500 stores across the UK and Ireland, are expecting problems sourcing the essential product due to a three-day ban on poultry shipments from Holland where many of its suppliers are based.
British farmers should prepare themselves for the possibility that more bird flu cases could emerge in the coming days.
Keith Warner, president of the British Veterinary Poultry Association, issued a warning ahead of today's duck cull at East Yorkshire's Nafferton farm.
He said: "Everybody in the UK that owns birds in any number should be on biosecurity lockdown."
Health experts have been pictured at a farm in Yorkshire where a reported bird flu outbreak has been confirmed.
Dressed in protective suits the health experts were seen at Nafferton farm yesterday ahead of today's planned cull of the 6,000 resident ducks.
It is believed the current bird flu outbreak, which has also affected the Netherlands and Germany, was brought to Europe by wild swans migrating from Asia.
The bird flu outbreaks in Britain and the Netherlands may have been brought to Europe by wild swans migrating from Asia, the European Commission has said.
Millions of farm birds in South Korea were destroyed after an outbreak of the H5N8 bird flu earlier this year.
The European Commission said: "A species of wild swans might be carrying the virus without showing signs of disease."
The European Union has praised the Dutch and British responses to outbreaks of bird flu in both countries.
A EU spokesman said: "We can say that all the protocols were followed and we can only praise the behaviour of the authorities of the two member states."
The European Commission has introduced emergency measures after the H5 strain of the virus was confirmed at a duck breeding farm in Yorkshire and the H5N8 strain at a chicken farm in Utrecht.
Authorities are investigating whether there is a link between the outbreaks.