(NewsNation) — More than a dozen schools in South Carolina reported being targets of a swatting hoax this week — and it’s something other schools have faced as well.

“Swatting,” as defined by the FBI, is when someone calls 911 and fakes an emergency that draws a large response from law enforcement, or even a SWAT team.

“Needless to say, these calls are dangerous to first responders and to the victims,” the FBI said.

On Wednesday, a wave of hoax emergency calls about school shootings sent hundreds of police officers into schools. These calls affected more than a dozen districts from Charleston to Greenville.

Parents rushed to the schools, the Associated Press reported, and the resulting police response disrupted the entire school day for some districts.

In Richland County, South Carolina, about 150 officers responded to a high school after getting a spoof call that appeared to come from inside the building, alerting police to an active shooter in a specific classroom.

Richland County Sheriff Leon Lott says although the threat is fake, the emotion and fear caused by the calls is real.

“We had to respond the way we did,” Lott said.

The FBI is now helping local police figure out who’s behind these calls, but they can be tough to trace.

“Active shooter situations are taken extremely serious by law enforcement. False claims aren’t a joke and prosecutors across the state will not treat them as jokes,” South Carolina Attorney General Alan Wilson said on Twitter. “I am disgusted by the recent numerous reports of false active shooter situations at South Carolina schools.”

South Carolina Gov. Henry McMaster says the hard part is finding out who’s doing the swatting.

“If they’re outside of the country, of course, that makes it more difficult,” he said.

No arrests have been reported yet in these cases.

Wired Magazine compiled a list of 92 false reports to schools across 16 states from Sept. 13 through Sept. 30. Of these calls, at least 32 appear to be linked to a single group or perpetrator, Wired reported. Most police departments did not provide the news outlet with records or respond to requests to confirm details about the contents of the calls, though, so the actual number of them linked to a single swatting campaign could be much higher, the magazine said.

Law enforcement experts say the only way to try to stop this trend is to find whoever is behind it and bring them to justice.

“I think to some extent, deterrence has to be: if you are able to identify an individual and prosecute that individual, that person needs to go to jail,” former FBI special agent Stuart Kaplan said.

The Associated Press contributed to this report.