A strain of avian flu has been identified in two Sonoran poultry facilities.

Federal food safety officials said that cases of the H5N1 flu were also found in birds at a facility in the Mexican border state of Nuevo Leon.

All three facilities have been quarantined, and nearly 300,000 birds were killed to prevent the spread of the virus. Production will not resume until the absence of the virus can be confirmed. In March, the U.S. Centers for Disease Control and Prevention said that it believes “that the risk to the general public’s health from current H5N1 bird flu viruses is low.”

On Sunday, Sonoran Gov. Alfonso Durazo said the state government would be working closely with the federal government to minimize the impacts of the infections.