Nogales Arizona, US Customs and Border Patrol agents found 254 lbs. (114kg) of fentanyl.
The drug was found hidden Saturday morning in a compartment after a scan during a secondary inspection indicated some anomalies in the load.
The traffickers tried to hide the drugs in a load of cucumbers, and the agency’s police dog team alerted officers to the presence of drugs in the truck.
Agents also seized nearly 395 pounds (179 kilograms) of methamphetamine. Most of the seized fentanyl, with an overall street value of about $3.5 million, was in white powder form, but about 2 pounds of it (1 kilogram) was contained in pills.
Fentanyl has caused a surge in fatal overdoses around the U.S.