The deadly Russian street drug krokodil is rumored to be making inroads in America even though the Drug Enforcement Administration has not officially confirmed the toxic substance is in the country. According to the Chicago Tribune, there are numerous cases of “crocodile drug” use in Illinois.

Two sisters from Joliet, Ill., Amber and Angie Neitzel, were the first self-proclaimed krokodil users to come forward and claimed they used the drug. At first the girls didn’t know they were using the flesh-eating drug, they told the website, but it happened to be cheaper than heroin and gave them a more intense high.

The fact that users aren’t sure of what they are shooting up was echoed by a psychiatrist with Centegra Physician Care, Dr. Paul Berkowitz, who told the Chicago Tribune it was possible people could be using the drug, which some say turn people into "zombies."

"There were significant skin changes — necrotic tissue, tissue damage," he said about one of his patient’s skin. "That was the sign that got us thinking that this might very well be krokodil rather than garden-variety heroin."

The patient, whose name and sex has not been revealed, had multiple lesions that were several square inches in size, as opposed to the coin-sized lesions that occur on a person from bad injection hygiene. Berkowitz said it was a “clinical suspicion” to say the patient might have used krokodil, which is an opiate like heroin and Oxycontin.

Though headlines everywhere are reporting the drug is allegedly in the country, Kathleen Kane-Willis, director of the Illinois Consortium on Drug Policy, told the Chicago Tribune on Tuesday she remained skeptical.

"I can't tell you how many calls I am getting. ... But people I talk to who are active drug users, and people who work with active drug users every day, are saying they have not heard of it (krokodil) being out there," she said.

Kane-Willis said krokodil, a homemade concoction of desomorphine and other toxins, became popular in Russia because heroin is hard to find, but in Chicago heroin is cheap and available.

The drug has purportedly killed two people in Oklahoma, though the cause of their demise has not been determined to have been from krokodil. Justin McGee, a father of four, and his unnamed friend may have been the drug’s first victims in America.