South Korea's government confirmed a fourth outbreak of the H5N1 bird flu virus in the country's southwest Sunday, as the tally of birds slaughtered to control the spread of the disease rose to 1.3 million. Government tests confirmed the latest H5N1 outbreak at a farm in Yeoungam, about 380 kilometers southwest of Seoul, Agriculture Ministry official Kim Chang-sup said. Earlier this month, South Korea reported its first case of H5N1 in more than a year. Since then, three more H5N1 outbreaks have been confirmed, Kim said. Six further outbreaks were being tested for the deadly strain, he said. Quarantine workers have slaughtered 470,000 chickens and ducks at 20 farms within a 3 kilometer radius of the site of the latest outbreak, according to Ryu Chul-hyuk, an official of the South Jeolla provincial government. More than 1.3 million ducks and chickens have been slaughtered this month in H5N1 affected areas in the southwest, according to the ministry.