ALBANY, N.Y. (AP) -- Matt Dana was known around the Adirondack Mountain town where he grew up as a promising young police sergeant who worked hard to root out narcotics dealers. So it came as a shock to friends and co-workers when he died suddenly this summer and an autopsy attributed it to an overdose.

It wasn't from drugs, but from kratom, an herbal supplement sold online and in convenience stores, gas stations and smoke shops.

"It was the talk of the town. People were upset it was reported as an overdose," said Paul Maroun, mayor of Tupper Lake in the central Adirondacks 110 miles northwest of Albany. "It's not an illegal drug."

Made from the leaf of a Southeast Asian plant, kratom (pronounced KRAY-tuhm) is touted as an energizer, potent pain reliever, and tool to wean people with addictions off heroin and other opioids. It's also increasingly used recreationally, with users describing it as stimulating like coffee at low doses, and producing a sense of relaxation and mild euphoria at higher doses.

Dana's death has resonated far beyond Tupper Lake, striking fear among kratom advocates that it could be cited in an ongoing federal review to get it banned nationwide.

Six states already ban kratom, and the federal Drug Enforcement Agency proposed a ban last year, citing 15 previous deaths from 2014 to 2016. But that proposal was withdrawn after public opposition, including a letter signed by 62 members of Congress and a protest at the White House organized by the American Kratom Association.

This undated photo provided by the Tupper Lake Police Department shows Sgt. Matthew Dana.

The DEA will decide whether to proceed with a ban after the Food and Drug Administration completes an analysis of the supplement. The FDA said there is no specific timetable. Previously, the FDA has warned consumers that kratom can cause adverse health effects, including severe withdrawal symptoms.

"This is very personal to a lot of folks," said Pete Candland, executive director of the American Kratom Association, founded in 2014 to advocate for full consumer access to the herb. "There are so many people who feel kratom has literally saved their lives, whether it's getting them off an opioid addiction, relieving pain or helping with overall health and well-being."

Why the 27-year-old Dana was using kratom is not clear. His obituary noted that in addition to enjoying hunting and fishing, Dana had been a bodybuilder. YouTube videos by bodybuilders advocate using kratom to increase energy and "push through the pain."

Advocates of kratom dispute the coroner's finding that it caused Dana's death from hemorrhagic pulmonary edema, when there is blood and other fluid in the lungs. The kratom association contends other factors were at work in the 15 previous deaths cited by the DEA, and it has requested the coroner's report in Dana's case to have it reviewed by toxicologists.

Franklin County Coroner Shawn Stuart said that the only substance in Dana's system was a high level of kratom and that his only physical ailment was the edema. Stuart said Dana had been making the powdered Red Vein Maeng Da strain of kratom into a paste and eating it.

Because kratom is classified as a dietary supplement, not a drug, it has not been subjected to clinical trials documenting health effects. But the FDA urges health care professionals and consumers to report any adverse effects to its online MedWatch program. A 2014 alert from the FDA warned the supplement could lead to respiratory depression, vomiting, nervousness, weight loss and constipation. And it noted withdrawal symptoms may include hostility and aggression.

Pulmonary edema wasn't listed as an adverse effect.

Whatever the cause, Dana's death is still being mourned as a loss to Tupper Lake. High School Principal Russ Bartlett said he was the rare kid who comes back to the tiny community after college to make it a better place.

"He wanted to be one of those people he had looked up to," Bartlett said.

- By MARY ESCH, Associated Press