The attack on a Pittsburgh synagogue Saturday morning is the worst on worshiping Jewish people in American history, according to a Cincinnati professor and director of the American Jewish Archives.
"This is the first time in all American history that Jewish people apparently have been murdered while worshiping," said Gary Zola, who also teaches the American Jewish experience at the Hebrew Union College-Jewish Institute of Religion in Cincinnati.
Robert Bowers, 46, has been identified as the suspect in the mass shooting, according to law enforcement officials.
The shooting took place around 10 a.m. at the Tree of Life Synagogue in the Squirrel Hill neighborhood near downtown Pittsburgh.
Police have Bowers in custody after the rampage, which resulted in 11 fatalities and multiple injuries. Four of the six injured were police officers, three of whom were shot, according to the Pittsburgh Public Safety Department.
The Anti-Defamation League, an international organization fighting anti-Semitism, called the attack unconscionable.
"This is likely the deadliest attack on the Jewish community in the history of the United States," agency CEO Jonathan A. Greenblatt said in the statement.
Zola said before Saturday, the worst attack on worshiping Jews came in March 1960, when an explosive device that didn't detonate was thrown into a Gadsden, Alabama, synagogue. As congregants fled, the armed perpetrator waited outside and shot two, Zola said. No one was killed.
The FBI is treating Saturday's incident as a hate crime and is leading the investigation, Pittsburgh Public Safety Director Wendell Hissrich said at a news conference.
The gunman walked into the building and yelled "All Jews must die!" then began shooting congregants, according to Pittsburgh television station KDKA-TV.
Posts believed to be from Bowers’ Twitter account show derogatory remarks about refugees and Jewish people.
Shep Englander, the CEO of the Jewish Federation of Cincinnati, once worked at Pittsburgh's sister federation and lived in Squirrel Hill. He said about half of the city's Jewish population lived in Squirrel Hill.
Englander, who is returning from Israel Saturday, said by phone he texted the CEO of the Jewish Federation of Pittsburgh after he learned of the attack.
"He texted back he was at the scene, and the shooting was still going on," Englander said.
Dealing with emotions ranging from sadness to anger, Englander said the Jewish Federation of Cincinnati will provide emotional and material support to those affected.
The Jewish Federation of Cincinnati released a statement not long after the violence. "On this holy day of Shabbat – a day for rest and peace – our hearts are broken," the Federation wrote. "Our thoughts are with the families of the victims in Pittsburgh and with the entire Jewish community there as they cope with this unthinkable horror."
Zola said hatred for Jewish people has stewed in America throughout its history, but a resurgence and outward expression of that hate has been seen in recent years.
"This idea that, 'It’s OK to say and do things because we’ve been stifled, we haters, all these years by people who tell us we’re politically not correct and to hell with that, we’ll say and do what we want,'" Zola said.
"There’s always been hatred. What is definitely without question manifesting itself is a willingness to act out."
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