Thai officials on Monday confirmed the country´s fourth outbreak of bird flu this year, with the deadly H5N1 virus detected among chickens in a northeastern province bordering Laos.

Livestock officials said the fresh outbreak was discovered two weeks ago in domestic chicken raised on a farm in Mukdahan province, about 640 kilometres (400 miles) northeast of Bangkok.

"The results of the laboratory test confirmed Sunday that it is the H5N1 virus," a livestock department official said.

"All chicken, turkey and ducks raised on the same farm were destroyed together with roughly 70 eggs."

A statement by the livestock department said 42 chicken, 39 turkey and three ducks on the farm were slaughtered two weeks ago, and almost 30 birds were culled on a farm near the infection site.

Thailand reported its first H5N1 outbreak this year on January 15, with the second case found a week later. The third outbreak was confirmed early last month in central Angthong province.

The kingdom has not seen any human deaths from avian flu this year, but neighbouring Laos confirmed its second such death this year on Friday.

Thailand has been among the countries hardest hit by the deadly H5N1 strain of the virus, recording 25 human cases, 17 of them fatal, since the outbreak began here in 2004.

The last bird flu fatality was in August last year, when a 59-year-old farmer in northeastern Thailand succumbed to the virus.

Thailand was initially criticized for being slow to respond to bird flu, but now is considered one of the countries best prepared to battle the disease, with a stockpile of 1.5 million capsules of the anti-viral drug oseltamvir.

But bird flu badly hurt Thailand´s poultry industry, after countries slapped bans on raw Thai chicken after the 2004 outbreak. Thailand, once the world´s largest exporter of poultry, now only exports cooked chicken.