An increasingly popular synthetic opioid known as Pink is being sold online, according to NBC News.
Only four states—Florida, Ohio, Wyoming and Georgia—have banned the drug, also known as U-47700.
Pink is eight times stronger than heroin, the article notes.
The drug, along with other synthetic opioids, is being shipped into the United States from China and other countries.
The Drug Enforcement Administration (DEA) told NBC News it is aware of confirmed deaths associated with the drug in New Hampshire, North Carolina, Ohio, Texas and Wisconsin.
Last month the agency gave notice of its intent to classify the drug temporarily as a Schedule I substance under the Controlled Substances Act. The temporary ban gives the DEA three years to research whether the drug should be permanently controlled.
Illicit drugs increasingly are being traded in hidden online marketplaces known as “crypomarkets,” The Wall Street Journal reports.
Revenue for illicit drugs in these online markets has doubled since 2013, while transactions have tripled, according to a study released by RAND Europe, a policy research institute.
Crypomarkets are predominantly run by drug sellers in the United States, Australia and the United Kingdom.
Monthly revenue is estimated at between $12 million and $21.1 million.
Most of the revenue is being generated by customers purchasing drugs in large quantities, suggesting they intend to resell them. Marijuana sales represent 37 percent of total revenue, followed by cocaine and amphetamines.
These online markets have emerged since the Federal Bureau of Investigation closed the illicit online marketplace Silk Road in 2013.