The Nebraska State Patrol says the nearly 120 pounds of suspected cocaine and fentanyl that troopers seized last month turned out to be all fentanyl, a deadly opioid that federal officials blame for thousands of deaths nationwide.

The patrol says the stash was a record fentanyl seizure in Nebraska and estimates the drugs may have been worth up to $20 million on the street. The Drug Enforcement Administration says just 2 milligrams of fentanyl can be lethal.

The foil-wrapped packages were found April 26 in a semitrailer searched after a traffic stop along Interstate 80 near Kearney, 170 miles (270 kilometers) southwest of Omaha.

The patrol says such drug seizures save lives. The Centers for Disease Control and Prevention says fentanyl and its variants killed more than 20,000 Americans last year, and the number is increasing.