The Drug Enforcement Administration is issuing a warning over a new drug they say is ten thousand times stronger than morphine.
Officials say three people have died after overdosing on carfentanil.
The drug is normally used as a tranquilizer for very large zoo animals.
Experts say it is a hundred times more potent than fentanyl and is so dangerous that it even poses a risk to first responders who come into contact with it accidentally.
For more information on carfentanil, click here.