NEW HAVEN, Conn. (WTNH) — Multiple unfounded bomb threats were made over the weekend at Ivy League campuses across the country, university and law enforcement officials said, two days after a bomb threat at Yale University forced the evacuation of several buildings Friday afternoon.

The call at Yale came in at 1:51 p.m. to a non-emergency line, which usually indicates someone from out of the area, Interim New Haven Police Chief Renee Dominguez said. The caller claimed bombs were placed in several buildings, Yale University officials said.

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The FBI is working with New Haven Police to track down the caller who sent half the city into controlled chaos.

Among nearby businesses that were evacuated was Claire’s Corner Copia on Chapel Street said. It was terrifying for the staff and customers.

“They literally came in and said ‘turn off the stoves, turn everything off and get out,'” owner Claire Criscuolo said. “We had birthday cakes ready to be picked up. We had cupcakes ready to be picked up.”

Yale resumed normal operations Friday night, and all roads in the area reopened just before 7 p.m. Many nearby businesses shut down for the day, but some reopened.

But New Haven was not the only city targeted in the last few days.

On Sunday, Cornell, Columbia, and Brown universities alerted students to threats but deemed campuses safe a few hours later. All the universities had ordered evacuations of some buildings.

“Since Friday, there have been multiple other calls to other universities around the nation of a very similar nature,” New Haven Mayor Justin Elicker said. “Our police department is working closely with the FBI to identify what appears to be a pattern and potentially the same individual, but at this point, it’s hard to tell.”

Elicker said whoever is responsible faces felony charges and is now the subject of a nationwide hunt.

“We’ll be working hard in collaboration with other universities and Yale University and the FBI to identify this person,” Elicker said.

Policing expert and former Fairfield police chief Gary MacNamara said the investigation will likely look into whether this was a case of swatting: calling in false threats with the purpose of triggering a massive police response.

“Certainly we know there are people that just like to cause disruption and chaos, and they don’t understand the magnitude of the danger of having such chaos and disruption,” MacNamara explained.

For exhausted businesses still recovering from the pandemic and operating under prolonged staffing and supply shortages, that chaos is a reminder to take care of each other.

“Someone is just so angry, and that’s really sad,” Criscuolo said. “So, I’m praying and hoping that we’ll figure out ways to get along better and think of each other more and ourselves less.”

The mayor added that said no one complained about the closures and praised the police response.