The Guardian Angels, a private, unarmed crime prevention group, said it would start patrolling the New York borough of Brooklyn on Sunday following a series of anti-Semitic attacks.
Curtis Sliwa, who founded the organization in New York City in 1979, said the patrols would start at noon in the Crown Heights neighborhood and expand to Williamsburg and Borough Park later in the day.
The move came hours before five people were wounded in a stabbing attack during a Hanukkah party at a rabbi's house in upstate New York late Saturday.
The latest incident followed eight attacks on Jews in Brooklyn since Dec. 13, according to New York police.
The violence included victims' being struck in the face, the head and the back of the head, as well as at least one person's throwing a beverage at someone, police said.
"These attacks are taking place, and the cops have not been proactive at all," Sliwa said Saturday. "It comes from City Hall and the mayor. He's been just apathetic."
Mayor Bill de Blasio's press office responded in a statement Saturday, saying: "We have no tolerance for anti-Semitism in New York City.
"The best police department in the world has increased deployment in Crown Heights, Boro Park and Williamsburg, and has launched a new intelligence unit to prevent hate crimes from occurring," it said. "We will continue to work hand in hand with the community to keep our city safe."
Before the stabbings Saturday night, the latest attack occurred Friday, when a woman slapped three females in Brooklyn and told officers it was because they're Jewish, police said at a news conference.
The suspect, Tiffany Harris, 30, was charged Saturday with attempted assault as a hate crime, according to court records. She was released without bail.
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On Dec. 10, a couple opened fire at a kosher market in Jersey City, New Jersey, and exchanged gunfire with officers. The episode ended in the deaths of the two attackers, a police officer and three people who had been inside JC Kosher Supermarket.
Gov. Andrew Cuomo called the attacks "disturbing."
"This recent spate of hate-fueled crimes is even more disturbing as they occurred during the Hanukkah holiday, a time when Jewish New Yorkers gather to celebrate," he said in a statement Friday.
Sliwa said that local leaders of the Lubavitch Hasidic movement asked for his group's help and that he believed Guardian Angels patrols would halt the violence.
"We're a visual deterrence in our red berets and our red satin jackets," he said. "Nobody's going to commit an attack when we're around."
If they do, he said, "we'll physically restrain the persons responsible, make a citizen's arrest and hold them until the police arrive."