The dreaded Russian street drug krokodil reportedly has killed two men in Duncan, Okla., KSWO in Lawton reports. The deadly drug rots a user’s body from the inside out and is named for the reptile since the user's skin can turn scaly and green and flesh even rots off the bone.

The Oklahoma Bureau of Narcotics is currently investigating to see if krokodil is to blame for the death of Justin McGee, a father of four, and one of his friends, the station reported Monday. If the connection is confirmed by authorities, the Oklahomans could be the first U.S. victims of krokodil.  

The drug is a cheaper version of heroin, but three times more addictive and 10 times as potent. It’s been seen in Russia for nearly a decade, but is rumored to have made its way to a few U.S. states in the past two weeks. The DEA, however, denies the illegal substance is in the United States.

The Verge cited medical professionals who said eight cases of krokodil use have been reported in the U.S. recently and three deaths. The article didn’t cite McGee and the other Oklahoma man as victims.

Dr. Abhin Singla, an addiction specialist at Presence St. Joseph Medical Center in Joliet, Ill., told Patch he has treated people in the U.S. who supposedly used krokodil.

“As of late as last week, the first cases – a few people in Utah and Arizona – were reported to have been using the heroin-like drug, which rots the skin from the inside out,” Singla said.

He added: “It is a horrific way to get sick. The smell of rotten flesh permeates the room. Intensive treatment and skin grafts are required, but they often are not enough to save limbs or lives.”

Sad, gruesome photos of the drug’s nasty side effects have swept the Internet since the drug started to make headlines. Many of the people’s skin had rotted down to the bone and there’s even a graphic YouTube video of a man getting his decayed leg sawed off.