Authorities found more than $10 million worth of marijuana hidden in a shipment of frozen avocado pulp at a west suburban cold storage facility in Illinois.

Workers at the facility in Lyons called police on March 4 after they noticed a suspicious shipment had arrived, bearing instructions “for an urgent pick-up,” according to the Cook County sheriff’s office.

Sheriff’s police responded to the building on the 8400 block of West 47th Street with a narcotics-sniffing dog, which detected drugs inside the pallets, police said.

Authorities ultimately found 2,100 pounds of marijuana—more than a ton—hidden in roughly 1,500 packages of frozen avocado pulp, police said. The drugs were packed into flat bricks and covered in the pulp.

The drugs have an estimated street value of $10 million, police said. The U.S. Drug Enforcement Agency and sheriff’s police continue to investigate.