ST. PAUL (AP) - Minnesota has confirmed a fourth case of a turkey farm infected with a bird flu strain that's deadly to poultry.

 
     The Board of Animal Health says the highly pathogenic H5N2 virus was found at a commercial turkey farm in Nobles County in southwestern Minnesota.
 
     The operation had about 21,000 birds. The board said Thursday that the farmer noticed birds dying in one of the three barns on the farm and reported it. The rest of the flock will be killed as a precaution. 
 
     Officials say the risk to the public is very low and there's no food safety concern.
 
     The same virus has turned up at three other Minnesota turkey farms in the last few weeks. It has also been found in Missouri, Kansas and Arkansas and some western states.