The DEA’s most recent National Drug Threat Assessment found the purity level of illicit fentanyl in the U.S. drug market has increased and the amount of fentanyl found in counterfeit prescription pills has increased, making the nation’s top drug threat even more dangerous.

This week, the Centers for Disease Control and Prevention (CDC) issued a public health warning about prescription medications sold by online pharmacies. The public health agency said some online pharmacies could be selling prescription drugs tainted with the potent opioid fentanyl,

A federal agency is warning consumers about using illegal online pharmacies after an increase in sales of counterfeit pills made with fentanyl and methamphetamine. The warning comes after the death of one person who bought what she thought was oxycodone but died of fentanyl poisoning.