Thousands of Israeli Jews took legal action against Facebook in a New York court Monday, alleging it allowed jihadists to openly recruit and train terrorists and plan terror attacks on its pages.

Some 20,000 Israelis, organized by the Israel-based non-profit Shurat HaDin -The Israel Law Center - joined a civil lawsuit filed Monday in the Supreme Court for the State of New York, seeking an injunction against Facebook.

The law center wants to force Facebook not only to remove the terrorists' pages, but also to better monitor and block users who post videos glorifying and encouraging terrorist attacks, and publish messages with instructions on how to carry out an attack.

“The terrorists do not come on their own; they write posts and encourage their friends to kill Jews,” said Israeli attorney Nitsana Darshan-Leitner, director of Shurat HaDin. “Facebook has been transformed into an anti-Semitic incubator for murder.”

While Facebook is accused in the suit of “intentionally disregarding the widespread incitement and calls for murder of Jews posted on its web pages by Palestinians,” a spokesman for Facebook said the lawsuit is without merit.

“We want people to feel safe when using Facebook. There is no place for content encouraging violence, direct threats, terrorism or hate speech on Facebook,” the company said in a statement to FoxNews.com. “As a community of nearly 1.5 billion people, we have a set of Community Standards to help people understand what is allowed on Facebook, and we urge people to use our reporting tools if they find content that they believe violates our standards so we can investigate and take swift action.”

The company maintains it encourages users to report inappropriate or dangerous messages linked to pages, profiles or individual content and a team of safety experts prioritizes investigations by reviewing the most serious first.

But Israelis involved in the lawsuit believe more needs to be done, especially on the heels of a “wave of terror” that resulted in seven Israelis being brutally murdered and several dozen others victims of stabbings.

They point to lead plaintiff Richard Lankin, 76, who was shot in the head and stabbed multiple times Oct. 13, 2015 by Palestinian terrorists armed with guns and knives from East Jerusalem as he rode on a crowded Jerusalem bus.

Lankin, in critical condition, is being treated for life-threatening injuries in a Jerusalem hospital.Two other Israelis were murdered and more than 20 were wounded in that bus attack.

The lawsuit, filed by attorneys Robert Tolchin of New York, Nitsana Darshan-Leitner the director of the Shurat HaDin civil rights organization, and Asher Perlin of Fort Lauderdale, Florida, claims the plaintiffs "have been living in the crosshairs of a murderous terrorist rampage carried out by killers who attack people with knives, axes, screwdrivers, cars and Molotov cocktails for no reason other than that the attacker perceives the victims to be Jewish.

“Many of these murderers were motivated to commit their heinous crimes by incitement to murder they read on Facebook—demagogues and leaders exhorting their followers to ‘slaughter the Jews,’ and offering instruction as to the best manner to do so, including even anatomical charts showing the best places to stab a human being,” the complaint states.

Since Facebook uses algorithms that match users with personalized ads and connect them to potential “friends,” the company should have the ability to monitor and block such postings, the lawsuit said.

U.S. based software company GIPEC has developed software to monitor illegal activity on social media, which is used by law enforcement to identify terrorist-related pages and track piracy, counterfeiting and pornography.

A GIPEC company spokesman said there is no excuse for social media companies not to be pro-active in removing terrorist-related content immediately.

“Terrorist organizations are spending time and money and using American social media platforms to recruit and incite sympathizers and ‘lone wolves’ here in the United States and Israel and around the world,” said the GIPEC spokesperson. “The social media companies supported by advertising revenue have a moral responsibility to make their platforms safe from these horrific and directional posts that call for terrorist behavior that we have been witnessing over the past months.”

Hanan Yadin, an Israeli whose Texas-based company, Instinctive Shooting Int'l, LLC, trains military and law enforcement about terrorism related conflicts, said combating terrorism, both on the ground and virtually, is an ongoing challenge.

“I am not sure that anyone can stop this completely,” Yadin said, noting as one terrorist page is pulled down, another goes up. “This is a warfare game, psychological warfare – to instill fear and intimidation among the targets. It is also an effective and cheap tool to instigate and to recruit.”

Veryan Khan, editorial director of Terrorism Research & Analysis Consortium (TRAC), said Facebook is just one of many social media outlets being utilized by terrorists to spread their message of hate.

Others allegedly include YouTube, Twitter, MySpace, Instagram, Pinterest, Ask.FM, Tumblr, SendVid, Dump.to, Just Paste.it, Nasher.me, Scribid and a new web site, Telegram.

Terrorists have used these networks to release 19 different videos since Friday calling for attack on Jews in Israel, she said.

Khan believes Facebook is doing its best to monitor dangerous activity, but the challenge is that like playing the game “whack-a-mole,” as soon as one account is taken down, another opens.

Darshan-Leitner told FoxNews.com that Facebook is just the first of several social media companies that may be targets of future lawsuits by her group unless they begin to better counter terrorist postings and activities.