The strain of the bird flu virus leathal to humans has been found in Croatia, the European Union has announced. The virus, also known as avian flu, was discovered in wild swans found dead at a pond in eastern Croatia last week. Veterinary expert Vladimir Savic repeated a plea to Croatian poultry producers to "take this seriously" and keep their animals indoors. After tests committed in a UK lab, it was confirmed to be the H5N1 strain that has killed at least 60 people in Asia since 2003. Officials are bracing for an outbreak of the lethal strain in the EU, after it was recently discovered in EU neighbours Turkey, Romania and Russia.