The illegal shipment was first noticed during an X-ray scan of an inbound tractor trailer at the Fort Street Cargo Facility in Detroit. The paperwork for the shipment stated that it was “a shipment of foam pool toys,” Kris Grogan, branch chief for northern/coastal regions at CBP Public Affairs, told CNN. The tractor trailer was headed for Ontario, Canada, Grogan added.

When officers and a K-9 team investigated further, they discovered that there were no pool toys inside the boxes — just over a ton of marijuana and packing peanuts.

“This seizure underscores CBP’s long standing commitment to the border security mission,” Port Director Devin Chamberlain said in the news release. “The men and women of CBP continue to work diligently to keep our Nation and our communities safe.”