ACT for America, which the Southern Poverty Law Center designates as an anti-Muslim hate group, is spearheading several rallies across the country Saturday in what is slated to be the group's largest protest against Islam.
The "March Against Sharia" will take place in more than 20 cities, including New York, Dallas, and Atlanta.
In New York City, about 100 protesters and more than 200 counter-protesters verbally clashed in downtown Manhattan Saturday morning, as police officers stood between the groups.
The rally began with ACT for America supporters denouncing Sharia law and claiming that America was moving in the wrong direction.
While they were were speaking, counter-protesters were trying to drown them out using bullhorns and noise makers.
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Some anti-Sharia demonstrators yelled, "Commie scum!," while counter-protesters shouted, "Nazis!," according to NBC New York.
The nationwide "March Against Sharia" first gained widespread attention when the mayor of Portland, Oregon, moved to stop the local chapter from rallying. Ted Wheeler's decision came after two men were fatally stabbed as they tried to protect two women — one of whom was wearing a headscarf — from an anti-Muslim tirade.
The organizers of Portland parade eventually changed the venue to Seattle, citing "safety concerns" in Portland.
In Seattle, opposing groups protested outside City Hall on Saturday, according to NBC affiliate KING 5.
"We are not anti-Muslim. We are anti-radical Islam," said a March Against Sharia speaker outside City Hall, according to the station.
The other group, Seattle Stands with our Muslim Neighbors, began their demonstration in Occidental Square Saturday morning before making their way to City Hall.
"Muslims are welcomed here," some chanted.
One Twitter user filmed the chant, writing, "#MuslimsAreWelcomedHere being chanted."
At a rally on the steps of the Pennsylvania state capitol in Harrisburg, the atmosphere was tense, according to Reuters.
Barricades and a heavy police presence, including officers mounted on horses, separated about 60 anti-Sharia demonstrators from an equal number of counter-protesters, most of them in black masks and hoods, Reuters reported. Nearly a dozen men carrying sidearms belonging to the anti-government Oath Keepers were on hand, invited by ACT to provide security.
ACT for America, which has over 525,000 members and has boasted of its close ties to President Donald Trump, is organizing the marches. It has been considered a hate group by Southern Poverty Law Center for several years.
At a rally on the steps of the Pennsylvania state capitol in Harrisburg, the atmosphere was tense, according to Reuters.
Barricades and a heavy police presence, including officers mounted on horses, separated about 60 anti-Sharia demonstrators from an equal number of counter-protesters, most of them in black masks and hoods, Reuters reported. Nearly a dozen men carrying sidearms belonging to the anti-government Oath Keepers were on hand, invited by ACT to provide security.
ACT for America, which has over 525,000 members and has boasted of its close ties to President Donald Trump, is organizing the marches. It has been considered a hate group by Southern Poverty Law Center for several years.
"ACT demonizes all Muslims as terrorists who want to subvert the political system in this country," said Heidi Beirich, director of the Intelligence Project at the Southern Poverty Law Center. They disseminate lies and fallacies about Muslims to spread fear about the religion, she added.
The Islamaphobic organization has gained significant momentum since its founding in 2007 by Brigitte Gabriel, a Lebanese immigrant who has openly called Islam inconsistent with U.S law.
"A practicing Muslim who believes the word of the Quran to be the word of Allah … who goes to mosque and prays every Friday, who prays five times a day — this practicing Muslim, who believes in the teachings of the Koran, cannot be a loyal citizen of the United States," said Gabriel during a course at the Department of Defense's Joint Forces Staff College in 2007.
ACT for America did not return requests for comment from NBC News.
"These marches are concerning because of what they will mean to the Muslim community," Beirich said. "When an organization propagandizes an entire community, it tends to embolden some people to commit hate crimes."
But ACT, which brands itself as "the NRA of national security," protecting "America from terrorism," said in a statement that the upcoming march is about "human rights" and protecting women and children from Sharia — which they say is quietly taking a hold of U.S law.
ACT initiated the "Stop Shariah Now" campaign in 2008. The SPLC said the group's website described its mission "to inform and educate the public about what Shariah is, how it is creeping into American society and compromising our constitutional freedom of speech, press, religion and equality what we can do to stop it."
More than 13 states have introduced bills banning Sharia law as a result of the campaign, Beirich said.
"It is absolutely impossible for any religious law to take over U.S. law," Beirich said. "The Constitution stops it, there is a separation of church and state," she said.
Another staple of the group is the Thin Blue Line Project, which is a "Radicalization Map Locator" that lists the addresses of almost every Muslim Student Association (MSA) in the country, as well as a number of mosques and Islamic institutions. The project, accessible only to pre-registered law enforcement, describes itself as a "one-stop internet resource for information concerning the perceived threat of Muslim infiltration and terrorism in the country," according to the SPLC.
The organization also forbids any interfaith dialogue with Muslims based on their suspicion that all members of the faith are connected to the Muslim Brotherhood, an established international political Islamist group founded in 1928.
"If you or someone you know is aware of a church or synagogue involved in or considering interfaith outreach, please warn them about organizations and individuals connected to the Muslim Brotherhood," the organization said in a 2012 statement.
The group campaigned hard for Donald Trump, and after he won the election, they boasted of having a "direct line" to the president.
Gabriel even visited the White House and tweeted she was going there for a meeting.
The White House did not return requests confirming a meeting with Gabriel.
Former national security adviser Michael Flynn and current Trump adviser Walid Phares are ACT board advisers, according to the organization. And CIA director Mike Pompeo is "steadfast ally," said Gabriel in a letter to her base.
The nationwide march is one of the largest coordinated efforts by the ACT, despite a small expected turnout based on the event's Facebook page.
As of Friday afternoon, only 50 individuals said they are going in Atlanta, 64 in Indianapolis, and 68 in Chicago, on the event's social media page.
The largest number of people interested are in San Bernardino, with 231 slated to join.
"The protest being planned ... by a designated hate group are only designed to fan the flames of hatred and promote xenophobia incidents like what happened in Portland across this country. This is not a rally FOR anything; it's a rally AGAINST Muslims and American values," said Rabiah Ahmed, a spokeswoman for the Muslim Public Affairs Council.
"We know that the views expressed by these hate groups do not reflect the vast majority of Americans," she added, "and we know that groups like this are only blinded by their extreme hate and ignorance."
—Reuters contributed to this report.