The government has confirmed that a bird flu outbreak earlier this week in Iksan, 230 kilometers south of Seoul, was due to a virulent strain of the avian virus.

Agriculture and Forestry Ministry spokesman Lee Yang-ho said Saturday that the National Veterinary Research and Quarantine Service has found that the outbreak was caused by the H5N1 virus.

He said experts are trying to confirm if the virus is the highly contagious type.

Around 6,000 chickens were killed in Iksan after the outbreak was reported.

All chickens and other livestock on the farm have been culled and buried, while a tight quarantine is surrounding the affected area.

The ministry said nobody has reported symptoms of the flu.

The country had a bird flu outbreak between 2003 and 2004, that led to the culling of more than five million birds. No South Korean, however, has come down with bird flu.