The stabbing at a rabbi’s house in New York state was “domestic terrorism”, state governor Andrew Cuomo says.
Hatred based on race, colour and creed was an “American cancer spreading in the body politic”, the governor told a news conference.
He called for a domestic terrorism law in the state to prosecute such crimes.
At least five people were stabbed in the attack in Monsey, north of the city of New York. The attacker was later arrested in New York’s Harlem area.
Witnesses said the attacker burst into the house, which was hosting a Hanukkah celebration, pulled out a large knife and began attacking people.
Guests reportedly threw tables and chairs at the man, who then attempted to enter a synagogue next door before fleeing in a car.
However his vehicle registration was passed to police and license plate scanners picked up the car as it entered New York City, where he was detained.
What did Governor Cuomo say?
He described the attack as “very disturbing” but said it was not an isolated incident adding that hostility based on race, religion and immigration status was spreading across the country.
“It is domestic terrorism. These are people who intend to create mass harm, mass violence, and generate fear based on race, colour, creed. That is the definition of terrorism,” he said.
“Just because they don’t come from another country doesn’t mean they are not terrorists. They should be prosecuted as domestic terrorists.”
“We are not going to let this poison spread. No one else can defeat this county, but this country can defeat itself,” he added.
The attack came a day after New York police said officers were stepping up patrols in heavily Jewish districts following a spate of anti-Semitic threats and attacks.
Two of the victims were still in hospital, police said.
A man brandishing a machete attacked a Hanukkah celebration at the rabbi’s property in Monsey – an area with a large population of ultra-Orthodox Jews. The incident happened at about 22:00 on Saturday (03:00 GMT Sunday).
“The house had many dozens of people in there,” Yossi Gestetner, a co-founder of OJPAC for the Hudson Valley region, told the New York Times.
Aron Kohn, 65, was in the rabbi’s home at the time. He told the paper: “I was praying for my life. He started attacking people right away as soon as he came in the door. We didn’t have time to react at all.”
Mr Kohn said that the attacker then tried to enter a synagogue next to the house, but people inside had locked the door.
What other reaction has there been?
Letitia James, the New York Attorney General, said she was “deeply disturbed” by the situation.
“There is zero tolerance for acts of hate of any kind and we will continue to monitor this horrific situation,” she said in a Twitter post.
In Israel, President Reuven Rivlin expressed his “shock and outrage” at the attack.
“The rise of anti-Semitism is not just a Jewish problem, and certainly not just the State of Israel’s problem,” he said in a statement.
“We must work together to confront this evil, which is raising its head again and is a genuine threat around the world.”
The attack follows a series of anti-Semitic threats and attacks in and around New York City. On Friday Mayor Bill de Blasio announced extra police patrols in three areas of Brooklyn.
Responding to the attack in Monsey, Mr de Blasio said he could not “overstate the fear people are feeling right now”.
“We will not allow this to become the new normal. We’ll use every tool we have to stop these attacks once and for all,” he said.
The Jewish holiday of Hanukkah marks the victory of Judah Maccabee over the Syrian Greeks in the Second Century BC and the recapture of Jerusalem.
Are anti-Semitic attacks on the rise in the US?
On Friday New York city police’s hate crimes unit said it was investigating eight anti-Semitic incidents reported since 13 December.
They included a threat by a man who walked into an Orthodox Jewish community organisation’s headquarters in Brooklyn and threatened to shoot someone. In another incident a 30-year-old woman reportedly slapped three women in the face.
New York Police Department commissioner Dermot Shea has said hate crimes in New York City are up 22% this year.
“You see a swastika being drawn, you see a brick being thrown through a window, you see a woman walking down the street with her kids and having her wig ripped off,” he said.
Earlier this month officials in New Jersey said a gun attack that killed a detective and three people in a Jewish supermarket was being investigated as “potential acts of domestic terror, fuelled both by anti-Semitism and anti-law enforcement beliefs”.
In April a gunman killed a female rabbi and wounded three people at a synagogue in San Diego.
That attack came exactly six months after the deadliest anti-Semitic attack in US history, when a gunman killed 11 worshippers at the Tree of Life synagogue in Pittsburgh.
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