Florida investigators are saying that they recently have come across an “unprecedented” epidemic of synthetic marijuana overdose calls that resemble scenes from “The Walking Dead” zombie apocalypse TV show.

Investigators in Clearwater, Florida, have been responding to a myriad of calls featuring people slumped over in such stupefied states that they could barely talk or move, especially during routine patrols through Crest Lake Park, according to WTVT-TV. The investigators are attributing the epidemic to overdosing on a bad batch of synthetic marijuana, more commonly known as “spice.”

“We called the police because there was a guy screaming so gutturally I though he was going to pop a blood vessel,” Janet Gruhala, a Clearwater resident who frequently visits the Crest Lake Park to walk her dogs, told WTVT.

The police say that dozens have calls have come in the past week reporting people who were found so dangerously high that they had to be rushed immediately to local hospitals for treatment for the suspected spice overdose, WTVT reported. Clearwater investigators suspect that their epidemic may be related to a series of recent cases in Tampa, in which spice manufacturers changed up the ingredients in the drugs to such an extent that many of its users have no idea what they are actually smoking, according to WFLA-TV.

“The spike that we’re seeing and my personnel are dealing with on the road are unprecedented,” Major Eric Gandy of the Clearwater Police Department told WFLA. “Looked like one of our zombie movies … I had 15 people walking around in various states of incapacitation.”

Police told WFLA that this latest surge in spice overdoses is “wreaking havoc” at hospital emergency rooms as doctors are struggling to do their best with the increasing number of patients.

“We have noticed a serious uptick of Spice incidents lately that have turned into medical calls and it’s become a serious drain on resources for the police department for the fire department and then in turn for doctors say at Morton Plant Hospital where the patients end up,” police spokesman Rob Shaw told WTVT. “You wonder when somebody’s going to have a heart attack and die from some of these substances.”

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