It comes as demonstrators in Philadelphia stand in solidarity with those who were hurt in Boulder.
The Philadelphia Museum of Art steps have become very familiar to Dafna Ofer. For more than a year and a half, she and others have demonstrated at that site, calling for the release of Israeli hostages.
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"We still have 58 hostages in Gaza," she said. "We want to continue reminding them they are still there."
Ofer was participating in a demonstration on Sunday afternoon at the same time that people demonstrating for the same cause in Boulder, Colorado, came under attack. Police say a man threw Molotov cocktails to set several demonstrators on fire as he yelled "Free Palestine."
American Jewish Committee Philadelphia-area Regional Director Marcia Bronstein blames anti-Jewish rhetoric for attacks like that one.
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"Antisemitic, anti-Zionist language is dangerous, and, when it's left unchecked, it's deadly," said Bronstein.
The attack in Boulder comes less than two weeks after a Jewish couple was killed outside of the Jewish Capital Museum in Washington, D.C.
The Jewish Federation of Greater Philadelphia said in a statement to Action News that the two attacks have the same undertone of hate.
"These are not isolated events; they are a part of a dangerous escalation in antisemitism that threatens the safety and security of Jewish communities nationwide," the statement read in part.
Anti-Defamation League Regional Director Andrew Goretsky agrees.
"The ADL Center on Extremism has been checking the online rhetoric that has been celebrating what happened two weeks ago. Justifying it, and it's that type of justification that creates the type of environment for the firebombing to occur."
The Anti-Defamation League says since 2020, there have been 16 terrorist plots or attacks targeting Jewish people or institutions. Nine of those 16 have happened within the past 12 months.
The people targeted in Boulder were doing an event with the organization Run for Their Lives, which has a local group in Philadelphia. They host weekly runs to bring attention to Israeli hostages. Ofer has been to some of those events.
"They hold pictures in their hands," she said. "They walk around with Israeli and American flags."
She said -- even with the fear that the violence has caused-- attacks won't deter her from demonstrating to bring the hostages home.
"These were to cause fear in the Jewish community," she said, "but we are not going to be afraid."