This year, fentanyl is coming in like crazy, and it's going throughout the U.S. everywhere

we hear about addiction and overdose problems.

Michael Humphries is director of the Port of Entry in Nogales, in Southern Arizona.

At the port, tractor trailers idle as they wait to carry more than 30 million pounds

a day of tomatoes, grapes, and other produce into the U.S. from Mexico.

Every day, thousands of people enter the U.S. on foot and in cars, and some of those

vehicles and people are also carrying drugs like fentanyl.

We don't open the trunk and, hey, there's a bag of fentanyl powder or pills.

You know, we're looking at tires, gas tanks, roof, floor seats, anywhere you can imagine.

Humphries has decades of experience in trying to stop contraband at the U.S. border.

Synthetic opioids like fentanyl are hard to catch because they are so easy to conceal.

And smugglers have gotten really good at hiding these drugs, especially in passenger cars.

Vampires Joel Rose spoke with Humphries about this.

I mean, you're talking about in the engine sometimes, right?

In the gas tank, like deep in the vehicles.

We have disassembled engines before one time.

They pulled out two pistons from the engine.

The void created by that was filled with narcotics and the engine was still running.

Fentanyl is more potent and it's cheaper to make than organic drugs like heroin or cocaine.

And fentanyl seizures in the U.S. have been climbing, especially in California and Arizona.

How exactly is it getting across the border?

Our analysis, our intelligence continues to point to most of us being smuggled at the ports of entry.

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