WASHINGTON, Feb 7: A strain of bird flu has been discovered in chickens in a non-commercial flock in the US state of Delaware, but it is not the same deadly strain that is affecting humans in Asia, newspapers said on Saturday.

More than 12,000 chickens were quarantined and due to be destroyed after the bird flu strain, known as H7, was found at a farm in Delaware's southern Kent County, the Delaware State News reported on its Web site.

Delaware Secretary of Agriculture Michael Scuse told the newspaper that the strain was not the same one that has struck humans in eight countries in Asia and posed no threat to human health.

The H5N1 bird flu has killed 18 people in Asia, forced the slaughter of millions of birds and alarmed experts because it is so deadly.

South Korea, which is battling a deadly outbreak of the virus, reacted swiftly to reports of the discovery in Delaware, immediately halting imports of US poultry.

The suspension covers quarantine inspection of US poultry and related products, South Korea's Agriculture Ministry said on Saturday.-Reuters