(NewsNation) — Nearly 200 Jewish institutions over the weekend appear to be victims of a coordinated swatting effort based out of the United States, according to a confidential memo by the Federal Bureau of Investigation’s top spokesperson.

NewsNation obtained this memo, first reported on by ABC News, written by Assistant FBI Director Cathy Milhoan and sent to partner law enforcement agencies.

“At this time, based on similar language and specific email tradecraft used, it appears the perpetrators of these threats are connected,” Milhoan wrote. “Additionally, these threats appear to be originating from outside of the United States.”

Non-profit Secure Community Network, a homeland security and safety initiative for the Jewish community, said it tracked over 199 swatting incidents and false bomb threats across the country that targeted Jewish facilities. The organization reported in a news release more than 449 swatting incidents in 2023, up from 541% in 2022.

What is swatting?

Swatting, according to the FBI, is where a hoax call is made to emergency service, or a fake threat is made, with most reporting an immediate threat to human life. The FBI Las Vegas Office said those who engage in swatting often say hostages are about to be executed or bombs are about to go off.

“Swatting may be motivated by revenge, used as a form of harassment, or used as a prank, but it is a serious crime that has serious consequences,” the FBI Phoenix Field Office said in a news release. The goal is to draw a response from law enforcement, usually a SWAT team, to a specific location.

Earlier this year, the FBI created a national database as swatting became more common, NewsNation partner The Hill reports. Advances in technology, The Hill writes, have made it more difficult for law enforcement to catch swatters, as people can mask their identities by using fake voices and obscuring their computer’s IP address. Some offenders even use “spoofing” technology, the FBI said, to anonymize their own phone numbers and make it seem as if an emergency call is coming from someone else’s phone number.

Why is it dangerous?

Swatting is dangerous to both first responders and victims, the FBI said.

Responders have to “rush to the scene” where a fake crime was reported, the FBI Las Vegas Office wrote, which takes them away from real emergencies. Officers can be put in dangerous situations, as “unsuspecting residents may try to defend themselves,” the FBI Office said.

“The alarming volume of swatting incidents and false bomb threats being carried out across the country is a major concern for the safety and security of the Jewish community in North America, as well as law enforcement,” SCN said in a statement. “It’s critical to recognize that these are not victimless crimes or innocent pranks: they can have real — and even deadly — consequences.”

At least four students at Harvard were held at gunpoint in May by campus police officers after a false police call about an armed individual in campus dorms. In 2021, a 60-year-old Tennessee man died of a heart attack after police raided his house because of a swatting incident.

What can be done about it?

Those who receive a swatting threat, or have information that someone is planning to engage in one, should report it to local law enforcement or the FBI at 1-800-CALL-FBI.

The FBI’s Phoenix Field Office also suggests: Using complex, different passwords and passphrases for online accounts, updating them regularly and using multi-factor authentication for all online accounts or any device that involves the Internet.

If someone’s smart device or email was compromised, they can report it to the FBI’s Internet Crime center at www.ic3.gov.