A suspect has appeared in a New York court charged with five counts of attempted murder over a stabbing incident at a rabbi's house.
Grafton Thomas, 37, allegedly entered the property in Monsey, Rockland County, during celebrations for the Jewish festival of Hanukkah, injuring several people with a machete before fleeing.
He was ordered held in custody after appearing in Ramapo Town Court, where he denied the charges.
The attack was quickly condemned as another incident underscoring growing anti-Semitic violence in the United States.
VIDEO of the vehicle driven by the attacker. Note the plate/tag digits. Thank you all who shared our earlier tweet. pic.twitter.com/PGgOhBD3qO
— OJPAC Hudson Valley (@OJPACHV) December 29, 2019
President Donald Trump tweeted that Americans "must all come together to fight, confront, and eradicate the evil scourge of anti-Semitism."
New York Governor Andrew Cuomo told reporters at the scene that "these are people who intend to create mass harm, mass violence - generate fear based on race, colour, creed."
No official details were released about the victims, who were taken to nearby hospitals. Local media said one person was seriously injured.
Mr Thomas was reportedly arrested in his car about 50km away, two hours after the attack.
One witness told how the weapon had a big handle and the attacker "swung it back and forth."
Joseph Gluck said: "Everyone was screaming and panicking and shouting 'out out out.' It was chaos."
I am horrified by the stabbing of multiple people at a synagogue in Rockland County tonight.
— Andrew Cuomo (@NYGovCuomo) December 29, 2019
We have zero tolerance for anti-Semitism in NY and we will hold the attacker accountable to the fullest extent of the law.
NY stands with the Jewish community. pic.twitter.com/JILUoFXJc9
Last year, a white supremacist walked into a Pittsburgh synagogue and shot dead 11 people - the deadliest attack against the Jewish community in the US.
Earlier this month six people, including the two attackers, were killed in a shooting at a kosher deli in Jersey City, New Jersey, which authorities said was fuelled in part by anti-Semitism.
A report in April from the Anti-Defamation League (ADL) stated that the number of anti-Semitic attacks in 2018 was close to the record of 2017, with 1,879 incidents.
Mr Trump denounced anti-Semitism after previous attacks but some critics say his rhetoric has played a part.
His daughter Ivanka and son-in-law Jared Kushner are Jewish.
But critics blame him for stoking racial hatreds with comments about Muslims and Latin migrants that some white nationalists have taken as confirming their position.
"I was praying for my life," said Aron Kohn, 65, another witness to Saturday's attack who compared the knife used by the assailant to "the size of a broomstick."
Mr Kohn threw chairs and tables in an attempt to head off the assault.
"I saw him stabbing people," he added. "He injured a guy. He was bleeding in his hand, all over."
Mr Kohn said the attacker tried to enter the adjacent synagogue, but it was locked.
Yossi Gestetner, of the Orthodox Jewish Public Affairs Council, told The New York Times that one of the victims was a son of the rabbi.
"The house had many dozens of people in there," Mr Gestetner said. "It was a Hanukkah celebration."
Rockland has the largest Jewish population per capita of any US county, with 31.4%, or 90,000 Jewish residents.
In response to the recent surge in hate crimes in New York, Mayor Bill de Blasio announced on Friday that the NYPD was stepping up patrols and increasing visits to places of worship.
After yesterday's attack, the mayor tweeted that he had recently spoken to longtime Jewish friends who were fearful of outwardly showing their faith.
"We will NOT allow this to become the new normal," he wrote. "We'll use every tool we have to stop these attacks once and for all."
In Israel, Prime Minister Benjamin Netanyahu said the country "strongly condemns the recent displays of anti-Semitism including the vicious attack at the home of a rabbi in Monsey, New York."
The attack happened on the seventh night of Hanukkah, with about 100 people gathered for a candle-lighting ceremony.
"It's a wave and a trend of hate-filled violence that is sweeping the country, not just NY State," tweeted Maya Wiley, a civil rights activist and senior vice president for social justice at the New School private university in New York. "We have to stand together to keep our neighbours safe."
