For decades New Jersey drug dealers were usually found in urban areas, because that's where most of their customers were, but that is no longer the case.

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"The folks who are using drugs these days, particularly when you're talking about the opioids, that's your suburban kids and your suburban adults," said Steven Liga, executive director of the Middlesex County chapter of the National Council on Alcoholism and Drug Dependence.

"What you have is supply and demand," Liga said. "If the demand is in the suburbs, that's where the suppliers are going to move."

Just as other retail markets change, according to Liga, so do drug markets.

"You've got a situation where your former urban drug dealer has a much stronger market in the suburbs, particularly for the more expensive and lucrative drugs like, say, heroin," Liga said. "You've got folks in the suburbs who have got more disposable income, and they're used to the opioids, coming from the expensive prescription painkillers."

The relocated city drug dealers do have some competition, though.

"You've also got your local drug dealers," Liga said, "who may have been doing marijuana and some other things saying, 'Hey, there's now a real market for heroin and I can get a good profit margin on that; maybe I'll expand my business.'"

Liga said many parents may be in the dark about their children using dangerous drugs like heroin, but it is becoming increasingly popular among teens and 20-somethings.