MINNEAPOLIS (WCCO) — Authorities are warning the public after five fatal overdoses in Minnesota were traced to a drug used to tranquilize elephants.

Hennepin County Medical Examiner Andrew Baker said in a press conference Thursday that his office has linked five deaths between Jan. 30 and Feb. 17 to the synthetic opioid carfentanil.

The drug is 10,000 times more potent than morphine, and 100 times more potent than fentanyl, the synthetic opioid that killed Prince.

Baker says the drug, which is often disguised as heroin on the streets, is typically used to tranquilize large animals. It is not approved by the Food and Drug Administration for use in humans, and an amount as small as a couple grains of salt can kill a person.

He says routine toxicological testing didn’t initially determine a cause of death in those five cases.

Carfentanil (credit: CBS)

“In each of the five carfentanil-related fatalities we have detected, there was strong historical evidence and seen evidence to believe that we were dealing with an opioid overdose,” Baker said.

He says his office had to use a reference laboratory to screen for certain synthetic opioids since very few laboratories are equipped to do so. The presence of carfentanil was found in those five cases, and Baker says four to five more deaths may also be connected to the drug.

Of the five confirmed carfentanil-related deaths, all were adults between the ages of 23 and 43. Three of the deaths occurred in Minneapolis; one was in Dakota County; and one was in Rice County. The latter case involved the death of a 43-year-old Faribault woman on Valentine’s Day.

Investigators are working to find the source of this drug locally, but they believe it was purchased by drug dealer on the internet and possibly from China.

In light of the increase in opioid overdoses in Minnesota and throughout the county, authorities are urging people to purchase the opioid antidote Naloxone.

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Jeff Wagner