South Korea on Tuesday said it was expanding a cull of chickens and ducks to try to contain a damaging bird flu outbreak.
The H5N6 virus was first confirmed on November 18 at a farm in central South Korea and has since spread to farms around the country, with the total number of cases now standing at 28.
The agriculture ministry said in a statement that it has culled more than 4.4 million birds and would slaughter another 2.7 million.
Health authorities agreed to issue a so-called "standstill" order to restrict workers at poultry farms from moving around the country if the virus continues to spread, the ministry said in a statement.
There have been no cases of human infections from H5N6 in South Korea, although between 2014 and April 2016, the virus killed six people in China, according to the South's Centers for Disease Control and Prevention.
The World Health Organization warned earlier this year that the strain "has caused severe infection in humans" but added "until now human infections with the virus seem to be sporadic with no ongoing human to human transmission".
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