CHARLOTTE, N.C. -- It's no secret that America has a drug problem.
But federal agents have been surprised by the amount of Mexican heroin flowing into cities all over the country.
A Drug Enforcement Administration video from suburban Charlotte, North Carolina, shows a drug deal in progress. A woman walking through a shopping center parking lot has no idea she just strolled through a heroin sale.
An undercover agent posing as a buyer asks, "How much is that?"
"One hundred," the dealer replies.
"Alright, cool. 'Preciate it, man, thank you."
The dealer even put his phone number on the back windshield, but authorities say it's not the car that's for sale.
It's mid-sized cities like Charlotte, Columbus, Indianapolis and Nashville, with lower crime rates and increasing populations, that DEA agent Bill Baxley said are attracting a growing heroin trade from Mexico.
"There's an incredible customer base," Baxley said. "You have the trafficking organizations that can operate here without the threat of certain gang activity or turf wars that you have somewhere say like in Chicago."
Baxley said what makes these cities safe, attractive communities for people to move to also makes them safe places for drug dealers to move to.
Mexican heroin has become a cheaper alternative to pain pills, which go for $80 a pill on the black market.
Baxley showed us a slab of Mexican heroin seized by his agents worth more than $1 million. It's sold in tiny balloons for $10.
But the dealers selling it aren't hanging out on street corners. They use a modern sales model that Baxley compares to pizza delivery.
"If you need heroin, then you call a number, and someone will deliver the heroin to you, where you're at," Baxley says.
CBS News was there as an undercover officer posed as a heroin addict and arranged a buy. Then we rode along with the DEA and watched the deal for ourselves. The two cars parked in a shopping center and the dealer approached the undercover officer.
"Took less than 30 seconds, way less than 30 seconds, probably about 15 seconds for the whole deal to go, be on our way," the undercover agent told us afterward.
Charlotte police are still building a case against that dealer, but because dealers often are kept in the dark about who they are working for, law enforcement sometimes never reaches the bigger suppliers higher up the chain.