There has been a big effort over the past year to crack down on stores that sell synthetic drugs like bath salts and Molly's Plant Food, but investigators are now going after the drug makers.
And some might be surprised to find out where they say they caught them in a recent bust.
Last summer, Metro police and the Tennessee Bureau of Investigation padlocked almost a dozen Nashville convenience stores for selling synthetic drugs.
Now, investigators believe they know where many of those drugs were originating: a big warehouse in Hopkinsville, KY, right next to a children's daycare.
"There was something fishy about them the whole time. We always wondered and talked amongst ourselves and wondered what was going on down there," said nearby business owner Brent Harrell.
Federal investigators say five people were operating a huge international synthetic drug manufacturing operation, getting ingredients from places like China.
Then, they would allegedly ship products with names like Molly's Plant Food, K-4, Triple X, Bang Bang and El Cheapo to gas stations, convenience stores, adult book stores and smoke shops all around the world.
Investigators say the group was clever. They registered with the Kentucky Secretary of State, had a Facebook page called Toke-n-Roll and pretended to be a legit business.
"In the dumpster there were all sorts of vials and little packages that were all completely empty, so they were making something down there," Harrell said.
Prosecutors believe the group has been manufacturing at the site since at least 2010.
Now, they face a long list of drug and gun charges.
These cases are tricky because prosecutors have to prove the drugs are being sold for human consumption. But attorneys with the Department of Justice said the laws are becoming more strict, so they are cracking down and more cases like this can be expected.
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