Close to 300 pounds of suspected marijuana were found in a shipment of Ford and Lincoln vehicles in a railyard in southeast Detroit.
Members of the US Immigration and Customs Enforcement (ICE) department searched rail cars carrying 200 vehicles that had been shipped in from Mexico.
The 277 pounds of pot was concealed in rail cars in large, plastic-wrapped bricks.
Ford employees discovered the packages while offloading the vehicles and notified Woodhaven Police who called in Homeland Security and ICE.
No arrests have been made, but a number of leads are being followed up.
ICE Spokesperson Khaalid Walls says there is no indication the rails cars or the vehicles were destined for Canada.