Jon Ritzheimer, a well-known anti-Muslim activist who has been monitored by the FBI, is among the armed protesters occupying a federal building in Oregon. (Jon Ritzheimer)

Most of the men who joined the Bundy brothers in occupying the Malheur National Wildlife Refuge are relative unknowns.

There is, however, a glaring exception: Jon Ritzheimer.

But unlike his new compatriots in the standoff in eastern Oregon, nobody seems to have known that Ritzheimer — a patriotically tattooed Marine from Arizona with a penchant for posting melodramatic videos online — was passionate about federal land disputes.

What he has displayed extreme passion for is Muslims. Namely, expressing his contempt for them and their beliefs.

Last year, after two Phoenix residents carrying assault rifles were killed by police outside a Muhammed cartoon-drawing contest in suburban Dallas, Ritzheimer began making and selling T-shirts bearing a profanity-laced denunciation of Islam. In May, he organized a protest that drew about 250 mostly armed anti-Muslim demonstrators to a Phoenix mosque.

Ritzheimer — who carried a 9mm Glock 26 at the May protest — called it a patriotic sign of resistance against what he deemed the tyranny of Islam in the United States.

He later sounded the siren about the coming war with Islam.

“The likelihood for blood will be high,” Ritzheimer wrote on Facebook in August. “True colors will be shown once again when we step up to this common enemy who attacks humanity daily and enslaves it’s [sic] followers.”

Supporters call him a “true patriot.”

Critics consider him the next Timothy McVeigh.

“If this man were born in a different country he’d be a suicide bomber,” one YouTube user wrote under a video made by Ritzheimer as he prepared to trek to Oregon last week.

“He’s come out of nowhere to become the anti-Muslim movement’s hateful poster child,” Heidi Beirich, who heads the Southern Poverty Law Center’s Intelligence Project, told The Washington Post. “I think he’s potentially very dangerous. He often comes across as literally unhinged. He’s rabid about everything. If I was a member of federal law enforcement up there in Oregon, I would be very concerned.”

Reached by phone Monday night, Ryan Bundy confirmed that Ritzheimer was among the militants occupying the federal outpost near Burns, Ore., but noted that he didn’t know Ritzheimer personally and wasn’t aware of his history or his anti-Muslim views.

“Everyone is entitled to their personal opinions,” Bundy told The Post. “I’m not saying that I believe or don’t believe his personal views. He’s an individual on his own — and, in other words, you cannot say that what he believes is what we believe. He’s entitled to his own views.”

A stand-off between federal authorities and armed occupiers angry at the jailing of two ranchers continues in Oregon. (Reuters)

Ritzheimer could not be reached for comment.

The Southern Poverty Law Center’s Beirich said the fact that Ritzheimer has attached himself to the conflict in Oregon is puzzling.

Anti-government activists, she said, are not typically big fans of Muslims — but Islam isn’t “their No. 1 beef.”

“We don’t see much overlap between these causes,” she said. “Anti-government activists are usually focused on gun rights or federal land policies, or they don’t believe the federal government should be able to collect taxes.”

But Ritzheimer, she said, “is up there saying things like ‘we’re going to fight to the death.’ He’s taken his crazy from one world to the next.”

Perhaps Ritzheimer’s arrival at an anti-government standoff isn’t all that surprising.

His Facebook page includes a drawing of a Revolutionary War soldier with a body builder’s muscles and an assault rifle. There are also photos of Ritzheimer at Revolutionary War battle sites, and statements calling for the U.S. government to be overthrown.

In recent months, his screeds against the government have grown increasingly strident.

In September, he even threatened to perform a citizen’s arrest on Sen. Debbie Stabenow (D-Mich.) for her support of the Iran nuclear deal, Roll Call reported. At the time, Ritzheimer identified himself as a member of the Oath Keepers; the militia group responded by threatening to kick him out, according to the Washington Times.

In response, Ritzheimer posted a video raging against the Oath Keepers.

“I’ll save you the trouble,” Ritzheimer screamed during a six-minute diatribe, according to Talking Points Memo. “I withdraw my membership. Keep my $40. You guys are clowns.”

“You think throwing a vest on,” Ritzheimer said, picking up a bulletproof vest, “and going in and sighting your rifles in — you think that makes you a patriot? You have no initiative!”

He added: “I’ve worn my gear. I’ve done my time. That’s the easy part. You’re too busy rolling around out there shooting at tree stumps that you can’t sit there and do the real work — get an indictment. Present it to the sheriff. If they don’t uphold the law, that’s where the militia come in.”

Ritzheimer is a staff sergeant and former Marine reservist with two combat deployments to Iraq as a “motor vehicle operator,” according to personnel records that were requested and subsequently posted online by This Ain’t Hell.

Checkpoint reported Monday that Ritzheimer never earned a combat action ribbon — a personal award denoting that the recipient was fired upon by the enemy, either by small arms or indirectly, according to information released by the Marine Corps to The Post. He was, however, given a certificate of commendation for engaging three suspected insurgents after an improvised explosive device struck a vehicle in his convoy in 2005.

Since then, Ritzheimer has become known for his anti-Islam activism, which attracted the attention of the FBI.

In May, he organized a “Draw Muhammed” contest outside of a Phoenix mosque and encouraged attendees to bring guns.

“I’m going to tell everybody to utilize your Second Amendment [rights] in case we come under that much anticipated attack,” he said at the time.

When a mostly armed crowd of about 250 showed up, Phoenix police were forced to form a human wall between angry demonstrators on either side of the debate.

No injuries were reported, but Ritzheimer said he received death threats — and that he and his family no longer felt safe in their home.

I can’t let my kids grow up in a society where tyranny is reigning over; I’ve got ISIS posting my address. This is terrorism at its finest, right here in America,” he said. “My family has to go into hiding.”

He said he was being forced into hiding because “lone wolves” were being sent to “behead” him.

A subsequent fundraising campaign seeking $10 million to provide security for his family fizzled and was shut down three days after it had started, according to Raw Story.

But Ritzheimer is perhaps best known for the rant-filled videos he posts on social media, some of which rack up hundreds of thousands of page views.

In July, he filmed himself screaming about Islam and shooting a copy of the Koran with an assault rifle. Several months later, he did it again, using a pistol for a video designed to promote the “Global Rally for Humanity,” a campaign that organized protests at dozens of mosques and Islamic centers across the country.

Ritzheimer also has created a website dedicated to selling anti-Islamic merchandise, as well as T-shirts denouncing CNN anchor Anderson Cooper. Cooper had thumped Ritzheimer during an interview in May, questioning why, as a Marine, he had worked to bolster an Islamic government in Iraq if he hates the religion.

Another threatening video in November, directed at members of a mosque in upstate New York, prompted the FBI to begin tracking Ritzheimer’s movements, according to the New York Daily News. When he cut off communication with agents, an alert citing a “potential threat to law enforcement” was issued in New York, the newspaper reported.

“And Obama, you stupid sorry sack of s—, you wanna come out and say we’re all afraid of these poor little widows and orphans?” he said on video. “F— you. That’s not what’s coming over here. … And guess what? We’re f—— ready for them.”

Among his latest videos: a rambling, 13-minute diatribe full of fatalism and posturing. The message was posted on New Year’s Eve and showed Ritzheimer crying as he said goodbye to his family and reminded them that he swore an oath to protect the Constitution at all costs.

Between quoting the Constitution and decrying government oppression, he told his little girls that he missed them and was sorry for missing recent holidays. He reminded them that they need to be good for their mother.

“I’ve had to do a lot of soul-searching up here,” he said. “And I’m with good people, who’ve also had to do a lot of soul-searching — some people who have been doing this soul-searching for years… and I am 100 percent willing to lay my life down to fight against tyranny in this country.”

Several days later, Ritzheimer appeared in a Facebook video recorded in Oregon, saying: “I’m armed with the Constitution and with a camera.”

The federal land occupied by the protesters, he said, “belongs to We the People.”

He encouraged “patriots … to come together.”

He said the protesters had come in peace.

“We all want to go home to our families,” he said.

Standing in front of a U.S. flag, he reiterated that he was “armed with a Constitution and a camera.”

“So that if they try to come in here fully armed and create another Ruby Ridge or Waco event, we can be right there to put the truth out and hold them accountable. But we don’t want it to come to that. Nobody wants it to come to that.”

“We need to keep this peaceful,” he said.

“We will not fire unless fired upon,” he said.

This post has been updated.

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