A public warning issued by the Drug Enforcement Administration about a powerful Opiod linked to overdose deaths.

FOX's Lisa Brady reports: 

It's supposed to be used as an elephant tranquilizer, but the DEA says carfentanil is now linked to a significant number of overdose deaths in various parts of the U.S.

10,000 times more potent than morphine, 100 times more potent than fentanyl. The acting DEA administrator Chuck Rosenberg calling it crazy dangerous, warning it's often disguised as heroin and can also look like powered cocaine or come as a tablet in blotter paper or spray.

So they're also concerned about medical personnel responding to overdose calls accidentally being exposed or inhaling it. 

This follows a DEA warning earlier this year on fentanyl, which can also kill in very low doses and is also being mixed with heroin.

Lisa Brady, FOX News.