The Agriculture Department has closed offices in five states after receiving anonymous threats.
USDA spokesman Matthew Herrick says in a statement on Tuesday that the department had received "several anonymous messages" that raised concerns about the safety of USDA personnel and facilities. He said six offices are closed until further notice.
Herrick said the department is working with the Federal Bureau of Investigation and federal and local law enforcement to determine whether the threats are credible.
The closed offices are in Colorado, Connecticut, Maryland, North Carolina and West Virginia.