A flock of about 240,000 chickens owned by Tyson Foods Inc. in Kentucky tested positive for a highly lethal form of bird flu, government officials and the company said on Monday, widening an outbreak that threatens the U.S. poultry industry.

Infections in the chickens being raised for meat triggered more restrictions on U.S. exports, with China blocking poultry products from Kentucky. Last week, buyers like China and Korea limited poultry purchases from Indiana due to an outbreak at a commercial turkey farm there.

The broiler chickens in Fulton County, Kentucky, located near the border with Tennessee, were infected with the same H5N1 strain of highly pathogenic avian flu as the turkeys in Indiana, Kentucky officials said.