Carrying golf clubs, shovels and hockey sticks, several hundred University of Connecticut students gathered just before midnight in a cemetery, ready to do battle with menacing clowns they had heard might be lurking among the headstones.

Police determined that Monday’s clown rumors were a hoax. But dozens of similar reports have surfaced across the country, largely on social media. And authorities are being forced to take them seriously as a potential threat to public safety, particularly at schools, where principals have conducted lockdowns and canceled classes.

The approach of Halloween 2016 and creepy clown costumes makes matters even more interesting for police this year.

“There are many other emergencies and calls for service that troopers and other first responders need to get to without being misdirected to a prank,” Connecticut state troopers said in a statement.

Clown incidents have been reported this week at schools around the U.S., including Penn State University, where police said more than 500 students showed up early Tuesday to hunt for clowns.

Officials at Merrimack College in North Andover, Massachusetts, ordered students to shelter in place for more than 30 minutes Monday night and evacuated a dorm after social media reports that an armed clown could be on campus.

The clown situations “waste valuable resources and can lead to injuries to both first responders and members of the public,” Connecticut state police said. The pranks “can cause major disruptions leading to schools, businesses and neighborhoods being placed into lockdown unnecessarily.”

Sociologists say the panic over clowns, which may seem silly from a distance, is actually a new twist on a phenomenon as old as witch hunts.

“There is a sense that there is some evil force out there that we have to organize together to attack,” said Dustin Kidd, a sociologist and pop culture expert at Temple University. “If anything, it’s just distracting us from the real ordinary threats that we face in our everyday lives.”

Rich Hanley, a journalism professor and social media expert at Quinnipiac University, which also had a clown scare this week, said the fear is easily spread on social media.

Posts on Twitter, Instagram and other sites, he said, often contain videos, images and statements that lack any context, factual filters or important details that would be in an actual news report. In a closed social situation, such as a school or university campus, that can easily lead to a less than rational response, he said.

Hanley compared the situation to a “Twilight Zone” episode titled “The Monsters Are Due on Maple Street,” in which “the monsters were all in peoples’ heads,” he said. “People respond, looking for pitchforks to get the monsters.”

Because of that type of attention from the community, Hanley said, law enforcement must take the issue seriously.

“I don’t think they have a choice,” he said. He compared it to the practice known as “swatting,” in which someone calls 911 to report that a person is being held hostage at an address. Even though it’s a hoax, police, sometimes including SWAT teams, respond in force.

And it’s not just at colleges. A false report last month of a clown grabbing a woman by the throat and threatening Reading, Ohio, schools led to classes being canceled for the day.

A 13-year-old student at Utley Middle School in Rockwall, Texas, was charged this week with making a terroristic threat after posting a purported clown’s hit list. Police told Dallas-Fort Worth television station KDFW that the student put herself on the list and told authorities she was only trying to stop any “real” clowns from attacking her school.

Several teenagers in Connecticut were arrested Wednesday on charges of making threats, accused of posting clown hoaxes on Instagram that led to extra security at several school districts.

Police also warned that anyone making credible threats could be charged with a more serious felony under a law passed this year in response to the 2012 Sandy Hook school massacre. The law calls for up to 10 years in prison for anyone intending to cause the evacuation of a school or school grounds with a threat.

New Haven public schools banned clown costumes this Halloween season after an Instagram account emerged with pictures of menacing clowns and captions telling several area schools to “watch out” and “wait and see” whether the threats are fake.

School Superintendent Garth Harries said Tuesday that the posts have been disruptive to learning and to the school’s sense of security.

“There is no question that whoever is promulgating this is making threats,” Harries said. “We don’t believe there is any credible threat of violence, but they are still making people uncomfortable.”