
CROWN HEIGHTS, Brooklyn (WABC) -- The attack carried out during a pro-Israel demonstration in Boulder, Colorado that left 12 people injured, has sparked new fears in New York.
For Jewish New Yorkers, the risk is real and it's growing. Perhaps nowhere more so than in the ultra-Orthodox community in Brooklyn.
Patrols in Crown Heights are being stepped-up Monday night, as the community celebrates the festive, two-day holiday of Shavuot.
Worshippers declined on-camera interviews because of the holiday, but several told Eyewitness News privately that they are worried and have been worried for months.

The firebombing in Boulder, Colorado was the kind of attack that is largely unpredictable and very difficult to prevent. It's not unlike the execution-style murders of two young Israeli embassy staffers less than two weeks ago. They were shot to death by a man chanting, "Free Palestine."
The assailant in Sunday's firebombing allegedly told police he was out to murder Zionists. In April, a man was charged with torching the governor's mansion in Pennsylvania while Josh Shapiro, the state's Jewish governor, was asleep with his family.
Security was intensified nine days ago at Jewish institutions throughout the city.
Jews make up 10% of the city's population but are victims of nearly two thirds of the city's hate crimes.
"That's not acceptable. And what happened in Colorado was despicable. Our hearts go out to the families that are involved," Mayor Eric Adams said.
Scott Richman is the regional director of the Anti-Defamation League. He fears these latest attacks will inspire others, perhaps in New York.
"Here we have what essentially feels like a copycat crime," Richman said. "This is a stepped up effort here, and we need to be careful that that this doesn't happen in our city."
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