Federal agents made the largest seizure of fentanyl in US history over the weekend thanks to a drug-sniffing dog.
US Custom and Border Protection officials announced the record-breaking bust during a Thursday morning press conference.
Michael Humphries, the port's director, said a 26-year-old Mexican national has been arrested. Humphries said the drugs were hidden in a secret compartment in a tractor-trailer carrying cucumbers.
Humphries said the tractor-trailer was singled out for a secondary inspection, at which point an X-ray machine showed anomalies at the back of the trailer.
A K-9 unit was then brought in and a drug-sniffing dog detected an odor coming from a secret compartment.
When officers breached the compartment, they found 254 pounds of fentanyl and 395 pounds of methamphetamine.
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The fentanyl alone makes the bust historic. It's the largest amount ever seized in one go. The previous record was set in 2017, when Nebraska state troopers stopped a truck with 118 pounds of the super-strong opioid, according to NBC News.
Humphries said the fentanyl was valued at $3.5 million and the methamphetamine was valued at $1.1 million.
Underscoring just how important it was that the drugs were caught before coming into the US, Humphries explained that fentanyl is about 80 to 100 times more powerful than morphine and just a few grains are enough to kill a person.
The Mexican national who was transporting the load has not been named, but officials say he has been charged with two counts of possession with intent to distribute a controlled substance.
President Donald Trump tweeted about the bust on Thursday. "Thanks, as always, for a job well done!" he said.
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