Updated Tuesday, August 16, at 1:05 p.m. to include additional information about overdoses in Barre City. 

A potentially deadly strain of heroin is being dealt in central Vermont, the Northeast Kingdom and other parts of the state, according to state health officials.

The Vermont Department of Health issued a warning Monday morning after emergency responders reported at least 10 overdoses over the weekend that required more than one dose of Narcan to revive the person. The news release notes that some of those incidents have been linked to a strain of heroin labeled "Game of Thrones," which may be laced with fentanyl, a synthetic painkiller that can be up to 50 times more potent than heroin. 

Barre City alone saw nine overdoses, one of which was fatal, according to Police Chief Tim Bombardier. VTDigger first reported on this particular rash of overdoses.

"That’s highly unusual. It means there's some really bad stuff on the street," Bombardier said. His department is still investigating where the heroin that caused the overdoses came from.

He noted that police have seen "no consistency with regards to packaging," and they haven't seen the "Game of Thrones" label that the health department warned about. Some of the heroin recovered in Barre City depicted a handgun and was labeled "Training Day."

The state has been working to distribute the overdose-reversing drug Narcan, also known as naloxone, more widely. But the department cautions: "While naloxone can reverse an overdose, it must be given quickly and [be] followed up with a 911 call for an ambulance." The street drug's effects can last longer than naloxone, the department noted, and it can take more than one naloxone dose to help.

Health officials are also urging drug users not to inject drugs while alone or to mix drugs, and are encouraging drug users to test a drug's strength before using the entire amount.