FedEx is searching for radioactive rods used for medical equipment that went missing during shipment between North Dakota and Tennessee.

Memphis-based FedEx spokeswoman Sandra Munoz said Friday that the rods are used for quality control purposes for CT scans. She says they were likely misplaced, and there’s no indication the material was stolen.

She says the shipment was from Fargo, N.D., to Knoxville, Tenn., this week and the rods are in a metal cylinder that is about 10 inches tall and weighs about 20 pounds.

Munoz says as long as no one tries to open the metal container, the rods do not pose a danger.