NEW YORK — Hours after a knife-wielding man barged into a Hanukkah party in a New York suburb, stabbing five people, top officials condemned the crime as part of a disturbing trend. New York Gov. Andrew M. Cuomo called it "domestic terrorism," linking it to the recent spate of violence against Jewish people in New York.

Anti-Semitic attacks are on the rise around the country, leaving members of the Jewish community feeling frightened and unsafe. In New York City, anti-Semitic crimes have jumped 21 percent in the past year. According to the Anti-Defamation League, there were 1,879 incidents of anti-Semitism in the United States in 2018, including more than 1,000 instances of harassment.

“This is a national phenomenon that we are seeing and it’s frightening and it’s disturbing,” Cuomo said at a news conference Sunday. “If anyone thinks that something poisonous is not going on in this country, then they’re in denial.”

Experts say anti-Semitic violence has been rising for years. In 2018, a gunman stormed Pittsburgh’s Tree of Life synagogue, killing 11 congregants and wounding six others. It was the deadliest anti-Semitic attack in the history of the United States.

Last April, during the observance of Passover, a gunman killed a Jewish worshiper at a Poway, Calif., house of worship and injured three others.

A rash of attacks

And a string of attacks in recent weeks has left the Jewish community in the New York area particularly unsettled.

This month, David Anderson and Francine Graham went on a violent rampage at a kosher supermarket in Jersey City, killing three people inside the store. The pair have been linked to the Black Hebrew Israelites, a hate group that traffics in anti-Semitic tropes. Authorities said they also posted ­anti-Semitic and anti-police screeds online.

On Dec. 23, a 28-year-old man punched and kicked a 65-year-old in midtown Manhattan while yelling anti-Semitic slurs, police said. Steven Jorge was charged with assault in the second degree as a hate crime.

On Thursday, an Orthodox woman was walking with her 3-year-old son in Gravesend, a neighborhood in Brooklyn, when she was approached from behind by Ayana Logan, officials said.

Logan, 42, whacked the 34-year-old mother in the head, officials say, and delivered an ominous message: “You f---ing Jew. Your end is coming to you.” She was arraigned on charges of assault as a hate crime, menacing as a hate crime and endangering the welfare of a child.

A day later, 30-year-old Tiffany Harris slapped three Orthodox women in the face and head in Crown Heights, a neighborhood known for its heavy Orthodox population and history of racial tension.

Police were convinced of Harris’s motive because of what she told them after the incident. “I cursed them out,” Harris allegedly told officers taking her into custody. “I said ‘F’ you, Jews.”

These attacks, along with several others that did not result in an immediate arrest, are being investigated by the New York City Police Department’s Hate Crime Task Force.

In Orthodox communities around New York, families are “definitely scared and frightened,” Rockland County official Aron Wieder said in a phone interview.

“If you were to walk down any street in Rockland County in the Orthodox Jewish community you will feel it in the air,” he said. “Children are frightened. Parents are nervous to send their children to school,” he said. “You could literally feel it and maybe touch it even.”

Celebrations of the last night of Hanukkah would go on after sundown Sunday, he said, but would proceed with caution and a measured tone.

The spike in bias incidents against Jewish communities has law enforcement and elected officials wrestling with what to do.

Police plans

At a news conference, New York Police Commissioner Dermot Shea said he could not believe he was addressing the public about anti-Semitic violence less than a month after the Jersey City attack.

“It is truly to me surreal to be having the same conversation about hate, a conversation about intolerance,” he said in Brooklyn on Sunday, before elected officials gathered at an oversized menorah in Grand Army Plaza for a symbolic lighting. “This affects us all.”

New York Mayor Bill de Blasio said that an increased police presence would be applied to “houses of worship” in heavily populated Jewish communities in Brooklyn. In a Fox News interview Sunday, he said there is a “crisis of anti-Semitism” in New York and elsewhere.

The NYPD has created a unit “to focus on racially and ethnically motivated extremism, to find where these groups are and stop them before they can act,” the mayor said.

“An atmosphere of hate has been developing in this country over the last few years. A lot of it is emanating from Washington and it’s having an effect on all of us,” de Blasio said. He and other Democrats have blamed President Trump’s rhetoric for emboldening white supremacists and condoning hateful conduct.

“Donald Trump has tried to stir up hate and division in our country,” Sen. Elizabeth Warren (D-Mass.) said Sunday in Iowa, where she’s campaigning for the Democratic presidential nomination. “You can never draw the line straight from one place to another. But he has embraced hatred and unkindness among our people in ways that put Americans at risk.”

Trump, however, has pushed back against this charge. In the aftermath of an August rampage at a shopping center in El Paso in which 22 people were killed by a gunman who targeted Hispanics, Trump said his language “brings people together.” “Our country is doing incredibly well,” he said, according to an Associated Press report.

On Sunday, Trump tweeted: “The anti-Semitic attack in Monsey, New York, on the 7th night of Hanukkah last night is horrific. We must all come together to fight, confront, and eradicate the evil scourge of anti-Semitism.”

Others have said elected leaders in New York are not doing enough to protect the Jewish community.

Former state assemblyman Dov Hikind, who founded Americans Against Antisemitism, said on “Fox and Friends” that the mayor and governor are “literally taking advantage of us” by expressing concern but not preventing acts of violence.

“I won’t know what his plan is,” Hikind said. “For [de Blasio] to tell me, every time there’s an anti-
Semitic incident that he condemns it, that he feels the pain, and then he goes home and waits for the next incident and does the same thing, what is going to be done by the mayor, the governor?”