PORT HURON (WWJ) - It was an extraordinary find for U.S. Customs and Border Protection agents in Michigan: ancient Egyptian mummy linens.

The artifacts were seized on May 25, according to officials, during enforcement operations at the Blue Water Bridge.

CBP said in a news release that Canadian mail truck selected for inspection was found to be hauling five jars of ancient Egyptian mummy linen.

Working with a Washington, DC based archeological organization, investigators determined that the scraps of material were from sometime around the Ptolemaic Dynasty 305-30 BC.

So, are they illegal? Yes, authorities say, as the owner was unable to prove that the artifacts were removed from Egypt prior to April 2016, which is in violation of the Convention on Cultural Property Implementation Act.

As a result, federal agencies will be working to return the artifacts to Egypt.

While drugs are the most commonly seize item, CBP agents are responsible for enforcing hundreds of laws at and between international ports of entry. As part of that mission, CBP enforces bi-lateral agreements and import restrictions on certain foreign cultural property and archeological materials to prevent the illegal trade and trafficking of cultural antiquities and artifacts.

“This seizure of historical importance highlights the wide variety of federal laws that CBP is responsible for enforcing. I am extremely proud of our officers’ hard work during and after the discovery of these ancient artifacts” said Port Director Michael Fox.

No details were released as to where artifacts came from, or where they were headed. No charges were announced in connection with the case.