According to the Interfax news agency, 153 birds have died from the H5N1 bird-flu virus, at the Lobzenko poultry factory in a central region of the Black Sea peninsula Crimea.

The outbreak was the first reported case of bird-flu in Ukraine in 2008. A quarantine five kilometres in diameter was in effect encircling the plant and the nearby Rivne village.

The processing plant prior to the outbreak contained some 25,000 birds, an official from Ukraine's Ministry of Emergency Situations said.

Health workers were testing all birds at the Lobzenko factory. More than 4,000 chickens had been killed and their remains burnt by Friday evening.

The last incident of bird flu in Ukraine was registered in July 2006, when health inspectors detected the disease in domestic poultry in the eastern Sumy region.

Ihor Krol, a spokesman for Ukraine's Ministry of Emergency Situations, called on Crime residents to "remain calm", and promised "the situation is fully under control."

Ukraine's government by law must pay domestic fowl owners for birds taken for destruction because of bird-flu outbreak, but bird owners frequently complain compensation is difficult actually to receive, and is less than the value of the lost birds.

Earlier this week, Indonesia reported that the number of human victims who have died from the H5N1 virus has reached 96 people, which is the world's highest.

The most common way to contract the H5N1 virus is through contact with infected fowl. Although bird flu remains mainly an animal disease, experts said they fear the virus could mutate into a form that could spread easily from human to human, turning into a pandemic that could kill millions of people.

Avian influenza cases have been reported among birds in 60 countries over the past four years. Most of the 217 human deaths from the disease since 2003 have been reported in Asia.