Could America's illegal immigration crisis be fueling a heroin epidemic?

In the last decade, heroin use in young adults has more than doubled, while heroin-related overdose deaths have nearly quadrupled.

David Ward, director of the National Association of Former Border Patrol Officers, told Brian Kilmeade on "Fox and Friends" that drug cartels will charge a "fee" for helping illegal immigrants cross the U.S.-Mexico border. He explained that "fee" will often be carrying a backpack full of heroin into the U.S.

"The cartels have taken advantage of our southern border and have exploited our weak security," Ward said. "And in the process of bringing heroin in, they've set up, throughout the United States, distribution points in our major cities, which happen to be sanctuary cities."

Ward explained that heroin is very lucrative and has grown in popularity, particularly in rural areas, because pills such as Vicodin and Oxycodone have become more expensive.

Watch more above.

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