WINDSOR, ONT. -- More than $20 million in undeclared designer jewelry destined for a New York auction house was seized at the Detroit Windsor tunnel.

Customs and Border Protection’s (CBP) Office of Field Operations seized the jewelry worth $20.7 million on Monday, a U.S. Customs and Border Protection news release states.

“For the traveling public, this example underscores the importance of knowing what is in their possession when attempting to make entry into the United States, and declaring it accordingly,” said Port Director Devin Chamberlain. “Officers in Detroit did an excellent job in discovering and securing this high-value undeclared merchandise.”

CBP says the jewelry was meant to be appraised and eventually sold at the auction on behalf of the owner, a Canadian citizen.

The “undeclared and unmanifested” merchandise was found after an investigation revealed a courier service was hired to transport the package to a contact in Detroit who was to take the jewelry to its final destination.

The driver of the vehicle claimed they did not know what was inside the package, and was then returned to Canada.

The owner of the jewelry was notified the pieces would be seized based on a failure to declare the merchandise upon entry and importation contrary to law, CBP says.