The CDC is investigating what appears to be an accidental shipment of live anthrax from the Defense Department to laboratories in nine states, according to a CDC statement.

A private commercial lab working as part of a DOD effort to develop a new diagnostic test to identify biological threats was expecting to receive an inactivated agent, however, live Bacillus anthracis was delivered instead.

The CDC does not suspect any risk to the general public. A similar incident occurred in July 2014 when the CDC workers were exposed to live anthrax.