The U.S. Department of Agriculture said Monday it had identified instances of deadly bird flu in U.S. flocks, putting the poultry industry on high alert for more widespread outbreaks.

The USDA reported an outbreak of highly pathogenic avian influenza in a flock of about 240,000 birds at a commercial chicken farm in Fulton County, Ky. Tyson Foods Inc., the largest U.S. chicken processor by sales, confirmed that the farm housed the company’s chickens.