Threat Calls Against US Jewish Institutions – Using Masking Technologies

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Federal investigators believe the latest wave of threat calls against Jewish centers and schools around the country was a coordinated attack perpetrated using sophisticated technology to shield their identity. 

On February 27th, bomb threats were called into 30 Jewish community centers and schools in at least 18 states across the US, adding to a growing list of anti-Semitic incidents across the US this year. So far, nobody has been injured. The threats came in the form of a series of phone calls.

Paul Goldenberg, the national director for Secure Community Network, a homeland security initiative focused on the Jewish community, told BuzzFeed News that those responsible “are leveraging technologies that have made the investigation more challenging.” He added that investigators determined that some people calling in threats were using “spoofing,” a tactic where a call appears to come from a friendly or known source when it is, in fact, coming from somebody else.

While at first, it was reported that law enforcement officials believe the attacks were a coordinated effort, a law enforcement official evaluated later that a single person may be responsible for the threats, using “voice masking technology.” According to the, the threats were made using an internet calling service. The high-pitched, rambling voice on the telephone was disguised and garbled, and warned of a slaughter of Jews. The voice spoke of a bomb loaded with shrapnel and of an imminent “bloodbath.” Moments later, the caller hung up. Independent analysts, including extremism researchers and retired law enforcement officials, share that theory and said that, so far, they have seen no evidence of an organized effort.

Though some people had suspected that the calls were recorded and automated, there was evidence to the contrary. In Milwaukee, for instance, a switchboard operator asked questions and received responses from the caller.

There have been five waves of called-in bomb threats so far this year, according to the Jewish Community Center Association, totaling 100 incidents at 81 locations in 33 states and two Canadian provinces.

Goldenberg and other researchers tracking these incidents say the numbers seen this year so far are unprecedented. The FBI and the Justice Department Civil Rights Division said they are investigating the threats as possible civil rights violations.

The quotes analysts saying anti-Semitic commentary online before last year’s presidential election had gradually escalated into more sinister behavior toward the Jewish institutions, which have long prepared for threats and often employ private security. “You started out with the hostile tweets,” said Mitchell D. Silber, who was director of intelligence analysis for the New York Police Department. “You moved to the bomb threats against JCCs and other institutions, and now you have a physical manifestation at the cemeteries with the gravestones knocked over.”