Federal authorities say the search of a shipment to Phoenix Sky Harbor International Airport has led to the seizure of more than 200,00 counterfeit masks.
The fake N95 face coverings were supposed to go to medical workers across the country.
In October federal authorities working at Sky Harbor opened an inbound shipment and found masks supposedly made by 3M. Cooperation by the company that produces N95 face coverings helped agents figure out that the masks were fake, said a spokesperson for Homeland Security Investigations in a news release.
Early in December, federal authorities found another batch of the same counterfeit masks at an unidentified Arizona business. Authorities then recalled and seized pallets of fake masks that had already been shipped to health care workers.
No arrests have been made and the investigation is ongoing.
EDITOR'S NOTE: This headline has been updated to clarify that the Phoenix inspection led to the discovery of the 200,000 masks.