(NewsNation) — Law enforcement agencies are responding to reports of shootings at schools across the nation that turn out to be completely false.

It's a practice the FBI calls "swatting," which the agency defines as faking an emergency that draws a response from law enforcement — usually a SWAT team.

Even though these threats turn out to be a complete fabrication, students, staff and parents still feel the same fear when they see an enormous police response on campus. And law enforcement says if they get these kinds of calls, they don't hold back on their response.

In just the last few weeks, threats forced lockdowns at dozens of schools in multiple states, including several schools in Texas, Arkansas, California, Colorado, Florida, Missouri and Virginia, according to EdWeek.

Images out of Thomas Jefferson High School in San Antonio show parents rushing to embrace their students. Police later established that no shooting had happened — instead, some students had an altercation, but denied having or displaying a weapon. Frightened students, though, had already made calls to their parents, who converged on the school, where there were 29 school district officers and 58 city police officers.

One man even shoved his fist through a window to enter the building, lacerating his arm in the process, the Associated Press reported.

"Until law enforcement clears the location or satisfies it as a prank, they are going to go as if it’s real," Former FBI Special Agent Stuart Kaplan said. "That’s a very dangerous scenario for law enforcement, as well as the person on the other side of that."

Experts say some of the threats are discovered on social media or smartphone apps that can be tough to trace, and it's often juveniles behind the false reports.

"Every single time that phone rings and that is a possible active shooter, we have to accept that as the real deal and go," Kaplan said.

On Twitter last week, the FBI in Houston wrote that making threats of violence against a school has consequences — whether they're joking or not. If a suspect behind a false threat is a juvenile, they can face suspension, expulsion or even criminal prosecution. Adults can face serious legal penalties for swatting, including possible incarceration and fines.

Amy Klinger, director of programs for The Educators' School Safety Network, said it's important to reinforce to people that swatting is not a funny joke or prank.

"It's a really serious situation that jeopardizes a lot of people, and puts a lot of people at risk, as well as inflicting trauma and anxiety on the parts of all the individuals involved," she said. "So it is not something that needs to be taken lightly by anyone."

"You're creating this high level of anxiety, you're eroding the trust in the organization," Klinger went on. "Can they really keep me safe? Is this really a dangerous place? And it even exacerbates and creates more threats."

The Associated Press contributed to this report.