Health officials conduct an investigation at a village entrance in Iksan, south of Seoul November 23, 2006. South Korea's farm ministry said on Thursday it had discovered a suspected case of bird flu at a poultry farm in the southwest of the country, which could be the country's first outbreak in about three years. The sign reads,'Check, animal quarantine'. [Reuters]

South Korea has confirmed its first bird flu outbreak in three years after a strain of the avian virus was found in tests on dead birds.

"Tests conducted by the National Veterinary Research and Quarantine Service confirmed a bird flu outbreak caused by the H5N1 virus," Lee Yang-Ho, the spokesman for the agriculture ministry, told journalists.

"Despite the confirmation that the virus is the H5N1 strain, experts are trying to determine if this is a highly contagious type or a milder variety," Lee said.

The blood tests on affected birds were carried out after some 6,000 chickens on one farm died in three days -- the first suspected case since the country declared itself free of the disease last December.

The ministry said the remaining 6,000 birds on the farm in the southern city of Iksan, 50 kilometers (155 miles) south of Seoul, had been all culled and buried.

The ministry has banned shipments to and from the farms in the contaminated area, carried out quarantine measures and imposed restrictions on the movement of people and vehicles there.

Iksan City called for an emergency fund of some 17 million dollars from the central government to increase quarantine activity and provide financial assistance to affected farms, Yonhap news agency said.

It also expanded the cordoned-off zone from an area within a radius of three kilometers to eight kilometers and asked for manpower assistance from police and military authorities to control movements to and from this area, it said.

Iksan is a hub of the country's poultry industry, where 5.2 million chicken are being raised on some 440 farms.

More than 200 poultry farms are within 10 kilometres of the affected one, as is the country's top chicken meat processor Halim.

Halim supplies 20 to 25 percent of the country's demand for chicken and also exports cooked chicken to Japan and other countries.

Following the suspected bird flu outbreak, Japan suspended poultry imports and started requiring people arriving from South Korea to disinfect their shoes when entering the country.

The deadly H5N1 strain of avian influenza, which is spread through contact with sick animals, has killed more than 150 people worldwide since late 2003 and triggered mass culls of millions of poultry.