Earlier coverage and related @ NYTimes.com

3 Crime Scenes and 6 Dead: Rampage Stuns Jersey City Published Dec. 10, Updated Dec. 11, 2:10 p.m. ET

The violence ended at a kosher market where three bystanders were slain. The mayor said the attackers had “targeted the location.”  “Our officers were under fire for hours,” said the Jersey City police chief, Michael Kelly. 

Kosher Market Attack in Jersey City: ‘I Just Hope They’re Safe’ Published Dec. 10, Updated Dec. 11, 8:59 a.m. ET

​It was one of the most violent scenes in the city’s recent history.  For several hours on Tuesday, a section of Jersey City was on edge during a standoff with at least two armed men. In all, six people were killed.

Uneasy Welcome as Ultra-Orthodox Jews Extend Beyond New York, by Joseph Berger, Aug. 2, 2017

first photo caption: A woman and boy in the Greenville neighborhood in Jersey City, where several dozen Hasidic families from Brooklyn have settled. They are part of a major movement of ultra-Orthodox Jews into communities around New York City in search of more affordable places to live

excerpt of roughly 1/2 of the lengthy article because it provides good context for the current story:

JERSEY CITY — To the gentrifying stew of bankers, artists and college graduates who are transforming this once blue-collar city across the Hudson River from Manhattan, add an unexpected flavor.

In a heavily African-American neighborhood, 62 families from a number of Hasidic sects based in Brooklyn and rarely seen here have bought a scattering of faded but roomy wood-frame rowhouses whose prices are less than half what homes of similar size would cost in New York — roughly $300,000 compared with $800,000.

These families are pioneers in a demographic and religious shift that is reshaping communities throughout the region. Skyrocketing real estate prices in Brooklyn and Queens are forcing out young ultra-Orthodox families, which are establishing outposts in unexpected places, like Toms River and Jackson Township in New Jersey, the Willowbrook neighborhood on Staten Island and in Bloomingburg, N.Y., in the foothills of the Catskills.

The influx, however, has provoked tensions with long-established residents, as the ultra-Orthodox seek to establish a larger footprint for their surging population. Residents complain that investors or real estate agents representing the ultra-Orthodox community have been ringing doorbells persistently, offering to buy properties at “Brooklyn prices.” Jersey City, Toms River and Jackson have all passed no-knock ordinances barring such inquiries under the threat of fines or have banned solicitations altogether.

The mayor of Jersey City, Steven Fulop, said his town took pride in its diversity but had been concerned about “very aggressive solicitation.

[....]

New York City and the surrounding suburbs are home to the largest concentration of Jews in the country and because of their high birthrate — five or six children are common — Hasidic and other ultra-Orthodox Jews represent the fastest-growing subset. They are now estimated to number about 330,000 in New York City alone — one-third of the city’s overall Jewish population.

They have become a more muscular political and social force and have turned the generally liberal profile of the area’s Jews more observant and conservative. Lakewood Township, near the Jersey Shore, voted for Donald J. Trump last year by the largest margin — 50 percentage points over Hillary Clinton — of any New Jersey community, according to an analysis by NJ Advance Media.

Squeezed out of their traditional neighborhoods, ultra-Orthodox Jews have taken steps that have raised concerns as they settle into new communities.

Michele Massey, a former Jersey City councilwoman who is the executive director of an organization that oversees a commercial corridor along Martin Luther King Jr. Drive, said Hasidim had opened a synagogue on the avenue despite a recent zoning change forbidding new houses of worship.

“It’s not because they’re Jewish,” Ms. Massey said of her opposition. “It could have been any other religion or group. It was simply the zoning law. I’m a person of color. Obviously I don’t care who lives where.”

The Hasidim contend that they have been primarily buying boarded-up or vacant homes and that solicitations have come from outside investors, not from the families that have moved in. They support the city’s no-knock law and point out that the Hasidic families that have moved into the Greenville neighborhood are a minuscule fraction of the area’s 47,000 people, half of whom are black.

[....]

The other day, a Hasidic woman, Gitti B., was standing on her stoop watching several of her five children play with the children of a neighbor, Chaya H. Gitti said she was able to buy a house with four bedrooms, three bathrooms, a large dining room and a playroom for the same cost in mortgage, taxes and insurance as her $1,600-a-month, two-bedroom apartment in Brooklyn.

She and Chaya both said they had to lean on their Hasidic neighbors because they no longer lived among parents, siblings and cousins. When she had her last baby, Gitti said, her Hasidic neighbors pitched in, taking care of her children and preparing meals. Their non-Jewish neighbors have also been helpful.

“They told us when we have to put out our garbage, and they introduced us to their pets so we shouldn’t be afraid of them,” said Gitti, who, like Chaya, did not want her last name used to protect her privacy. “They’re nice people.”

Eddie Sumpter, 34, a black neighbor around the corner who was able to buy a bigger house by selling his previous home to a Hasidic family, said he welcomed the newcomers.

“We live among Chinese. We live among Spanish,’’ said Mr. Sumpter, who is a cook. “It don’t matter. People is people. If you’re good people, you’re good people.”