A Maryland man is facing possible life in prison after pleading guilty to threatening more than a dozen Jewish institutions in Philadelphia, Washington, D.C., and other locations in the Northeast.
Clift Seferlis of Garrett Park, Maryland, was charged with 17 counts of mailing threatening communications and eight counts of obstructing the free exercise of religious beliefs. He entered his plea before U.S. District Judge Mark Kearney in Philadelphia on Nov. 17.
Seferlis is scheduled to be sentenced on March 16. He faces a maximum penalty of 169 years in prison, three years of supervised release and a $5,650,000 fine, according to the U.S. Department of Justice.
Court documents say that between March 2024 and June 2025, the 55-year-old sent more than 40 letters and two postcards to at least 16 Jewish institutions, including synagogues, museums, community centers, schools, nonprofit organizations and a Jewish deli. Many of the letters threatened to destroy buildings or harm those inside, referencing the Israel-Hamas war, officials reported.
The Justice Department said Seferlis “intentionally obstructed and attempted to obstruct congregants and other attendees in the enjoyment of their free exercise of religious beliefs” by sending threatening communications to synagogues or other Jewish institutions in Philadelphia, Washington, several locations around D.C. and Brookline, Massachusetts.
The offenses against four of the synagogues included the threatened use of a dangerous weapon, fire or explosives.
Written on a typewriter, many of Seferlis’ letters contained newspaper clippings of articles about the war in Israel and Gaza. Some included references to Kristallnacht, the 1938 antisemitic attacks across Nazi Germany and parts of Austria, prosecutors said.
A postcard mailed from Philadelphia read, “Gaza is in ruins. Countless dead. And you want to tell your story. Your story soon will be trying to rebuild your building when we are done playing IDF on it. You ready?”
In a letter sent in May to a Philadelphia-based Jewish institution — reported by Philadelphia magazine to be the Weitzman National Museum of American Jewish History — Seferlis wrote, “The hatred toward you all, your [institution], and especially the nation of Israel is at an all time high and is only getting worse.”
He asked the institution’s staff if they really care “about what is going on in Gaza,” and inquired if it would take “something happening” to their “beloved” institution to “make that happen.”
The same institution received several additional messages, totaling six since April 2024, including a threat to physically destroy the institution, prosecutors said.
Other threatening letters to the institution and its employees, thought to be sent by Seferlis, referenced the institution’s “many big open windows,” Kristallnacht, “anger and rage” and a future need to “rebuild” the institution after its destruction.
Prosecutors added that Seferlis — a self-described tour guide who said he visited Pennsylvania often — told the FBI that he had led tours of the institution in the past and had been planning to do so again.
The Jewish Federation of Greater Philaldelphia welcomed the guilty plea and thanked those who worked to keep the Jewish community safe.
“The individual admitted to sending at least 40 letters and two postcards to more than 25 Jewish organizations over a 15-month period, each conveying threats of violence and destruction,” the Federation said in a written statement to the Jewish Exponent. “We are grateful to FBI Philadelphia and the partner agencies whose diligent work led to this outcome. Our Jewish Federation’s security team, working in coordination with the Secure Community Network (SCN), continues to support Jewish institutions in identifying and reporting potential threats. We also appreciate the vigilance of the institutions that reported these threats. The safety, security and resilience of our Jewish community remain our highest priority.”
This case was investigated by FBI Philadelphia, alongside FBI Baltimore, the United States Postal Inspection Service, the Montgomery County Police Department in Maryland and the U.S. Attorney’s Office in Greenbelt, Maryland.