New Hampshire state officials have confirmed the first deaths in the state from carfentanil – the most potent form of the synthetic opioid fentanyl. Carfentanil is commonly used as an elephant tranquilizer.

Two men in Manchester died from the drug on March 11 and March 13 and another man in Meredith overdosed on the drug on March 13, according to New Hampshire Attorney General Gordon MacDonald. State officials said the New Hampshire Medical Examiner was able to confirm the link to carfentanil on Tuesday and said there have been no arrests in the deaths so far.

“This is an extremely dangerous drug. It’s visually identical to fentanyl; however, it’s 100 times more powerful and, unfortunately, now it’s here in our state,” Gov. Chris Sununu said.

Carfentanil is most commonly used as a tranquilizer for elephants and other large animals. The drug is so potent that an amount smaller than a poppy seed can be lethal to humans. It is manufactured in Chinese chemical labs and has also been used by governments as a chemical weapon; the Russian government used carfentanil against Chechen separatists in 2002, according to the Associated Press.

In recent years, it’s been making its way into batches of heroin, as drug manufacturers cut it in to make more drugs and boost their profit margins. The drug has been linked to spates of fatal overdoses in states including Ohio and Maryland; however, it was not believed to be in New England prior to Tuesday’s conference.

New Hampshire State Police Forensic Laboratory Director Tim Pifer said he’s not aware of any other New England states reporting carfentanil deaths.

Sununu and Department of Health and Human Services Commissioner Jeffrey Meyers said first responders should exercise extreme caution when responding to overdose cases or crime scenes, because the drug can be lethal if it is absorbed through the skin or inhaled.

Meyer said his department has about 3,000 Narcan kits that are distributed to emergency providers across the state. He added that emergency responders have to administer much higher doses of Narcan to revive someone who has overdosed on carfentanil because the drug is so potent.

“We will take the steps that we need to do to ensure we have an adequate supply of Narcan,” Meyers said.

More than two-thirds of the state’s 478 drug deaths in 2016 were attributed to fentanyl use, which is already 100 times stronger than morphine. State officials warned that carfentanil is even more lethal.

“As a chemist, one of our biggest fears was when carfentanil would make its appearance in New Hampshire,” Pifer said. “Unfortunately, we’re here today to talk about the fact that it happened.”

Pifer said the drug can put down an animal that weighs 5 to 6 tons.

“You can imagine how deadly and potent it would be for an average male or female,” he added.

Pifer said the drug was confirmed on Tuesday when the state laboratory was able to obtain a sample of carfentanil to compare with the drugs that killed the three New Hampshire men.

State officials said they do not know if there are other deaths linked to the drug but are continuing to test more cases.

“Unfortunately, today is the first day that we’ve been able to confirm this, and worse yet, I think we all understand that it’s likely not the last day that we talk about this issue,” Sununu said. “People have to understand that it’s out there, resistant to basic injections of Narcan. That is a recipe for a disaster.”

(Ella Nilsen can be reached at 369-3322, enilsen@cmonitor.com or on Twitter @ella_nilsen.)