Creepy clown frenzy has reached the East Coast.

The furor apparently started in early August, first with a publicity stunt for a short film in Wisconsin, followed by more serious-seeming reports to police about clowns attempting to lure and chase children into the woods in South Carolina later that month.

Numerous reports of clown sightings to police or threats made by clown personas on social media have occurred in more than a dozen states and are consuming considerable law enforcement resources.

On Sept. 22, a teenager fatally stabbed a 16-year-old boy who was wearing a clown mask in Reading, Pennsylvania. The stabbing occurred during a fight about the mask, police said. A 19-year-old was charged with second-degree murder in the incident, The Associated Press reported.

In another case in Pennsylvania, the Department of Homeland Security was called to help investigate an incident involving several Instagram photos of creepy clowns with the inscriptions including “It’s time to kill,” and “Coming to Neuman Goretti on Monday!! Gonna shoot all the kids and teachers.” The investigation found Monday that a 13-year-old girl and a friend were responsible for the posts that she said were a “prank.”

One creepy clown sighting was confirmed in Newburgh, New York, on Saturday. A person wearing a menacing clown mask with orange hair was observed on a bridge holding what looked like a shotgun, but was later determined to be a BB gun. Police identified and questioned the person. No charges were filed.

Last week in Lindenhurst, New York, an elementary school was put on lockdown because of a threat on Twitter.

NYPD Deputy Commissioner John Miller addressed the issue Monday.

"There have been attempts to make threats over social media in New York City," he said, adding that the NYPD quickly concluded "none of them to be credible" and that the department is going to "avoid falling into the trap" of wasting resources on obvious hoaxes.

Miller emphasized that false-reporting and unnecessary use of police resources are both crimes.

This summer’s hysteria can perhaps be traced to Green Bay, Wisconsin, where in early August residents began calling police about a disheveled looking clown seen walking through town at 2 a.m. and holding four black balloons.

On a Facebook page devoted to sightings of that clown, commenter Sharon Mueller said that if she encountered this clown, dubbed “Gags,” she would “curl into the fetal position and die of heart exploding from pure terror.”

About a week later, a disgruntled actor reported to the media that Gags was a publicity stunt for a movie about a menacing clown—a role for which he was not cast, the film’s director Adam Krause told Metro.

The movie, a 16-minute short called “Gags the Clown,” had its premiere screening in Green Bay to a sold-out crowd on Monday night, Krause, 33, said.

Creating a clown panic “was the first step in our viral marketing,” Krause told Metro, adding that he does believe his media campaign kicked off the recent rash of clown shenanigans across the country.

“It’s very possible that it was our promotion,” because it “caught on like wildfire,” and attracted tens of thousands of likes on the Facebook page before it was revealed to be a stunt, he said.