South Korea said Sunday it culled more than 35,000 ducks at poultry farms in the centre of the country in order to curb a new bird flu outbreak confirmed last week.

A breeding farm in Cheonan, 90 kilometres (56 miles) south of Seoul, was confirmed Thursday to have been infected by the deadly avian influenza, the latest in a series of outbreaks despite efforts to stem the disease.

A total of 35,560 ducks were slaughtered for burial at the farm and four other neighboring farms within a 500-metre radius, said Lee Kwang-Sop, the Cheonan city official handling the culling.

"There is no sign yet of the bird flu spreading," Lee said.

The latest bird flu outbreak followed one reported on February 10 in Anseong, north of Cheonan, which was the latest in a series of H5NI cases reported since November.

More than two million birds have been culled at poultry farms in the country´s central and southwestern areas since a bird flu case was confirmed on November 25, the first in almost three years.

South Korea was hit hard by bird flu between December 2003 and March 2004, prompting the cull of 5.3 million poultry and costing about one billion dollars.