At first glance, five killings in three states since last May appeared to be unrelated, isolated cases.

But a common thread is emerging. Three young men have been charged, and all appear to have links to the same white supremacist group: the Atomwaffen Division.

Atomwaffen is German for "atomic weapons," and the group is extreme. It celebrates Adolf Hitler and Charles Manson, its online images are filled with swastikas and it promotes violence.

A video on its website shows young men in face scarves and camouflage firing rifles during military-style training. The video begins with group members shouting in unison, "Race War Now," and concludes with the tag line, "Join Your Local Nazis."

"Atomwaffen no doubt takes some of the white supremacist rhetoric to another level. The views that they articulate are white supremacists on steroids," said Joanna Mendelson, who follows extremist groups for the Anti-Defamation League in Los Angeles.

"And what is the change they want to see? Real-world violence. Real-world apocalyptic violence," she added.

Radical Islam and neo-Nazi attacks

In the public conversation about extremism, radical Islamists get most of the attention. But according to a U.S. government report and private monitoring groups, right-wing extremists have carried out a similar number of killings since 2001.

The First Amendment protects the free speech rights of neo-Nazi groups like Atomwaffen, which was formed in 2015.

Group members hide their identities and may not even know one another beyond their online pseudonyms, although some have gathered for weapons training.

According to various estimates by monitoring groups, Atomwaffen is believed to have fewer than 100 members scattered across the country, with Florida and Texas considered key areas.

And it keeps popping up in the news.

In Orange County, Calif., prosecutors say 20-year-old Sam Woodward stabbed to death 19-year-old Blaze Bernstein on Jan. 2.

They had attended high school together and apparently went to a park on the night of the killing. Bernstein was Jewish and openly gay. He was back home for winter break from the University of Pennsylvania.

"Blaze was a brilliant, colorful and charismatic man who shined light on all of the lives, and people and communities that he touched," Bernstein's father, Gideon Berstein, said at a news conference just days after his son's death.

According to the news outlet ProPublica, Woodward was an Atomwaffen member who attended one of its training camps. Group members are supporting him on social media.

Five killings

This is the most recent of three separate attacks, and a total of five deaths, with apparent links to Atomwaffen.

"All these young men, steeped in this propaganda, both online and off, went on to enact violence," said Keegan Hankes, who studies far-right groups for the Southern Poverty Law Center.

"The fact that so much of it came to light in a short period of time shows how devastatingly potent some of these materials can be," he added.

As far-right groups try to expand, they are operating more openly, he said. One tactic is posting flyers on college campuses. The purpose appears two-fold.

Groups believe they'll find some recruits, and provoke outrage among others, generating the notoriety they seek.

"That's why you see them trying to drive media attention, because it may get an angry disaffected young man to go to that forum and further go down that rabbit trail," Hankes said.

In Reston, Virginia, just outside Washington, police say a couple was fatally shot in December by their daughter's 17-year-old boyfriend.

The shooting took place after the couple told their daughter to break up with the boy when they learned of his neo-Nazi beliefs — reportedly linked to Atomwaffen.

The accused, who's not being named because he's a minor, shot himself in the head, but has survived. According to Hankes, he appears to be mostly a sympathizer with Atomwaffen, though at least one report said he was in direct contact with the group.

A double-murder in Florida

Atomwaffen first came to public attention in a double-murder case last May in Tampa, Fla.

Devon Arthurs, 19, was charged with killing two roommates. He told police he was an Atomwaffen member — and bizarrely — also a convert to fundamentalist Islam.

He's pleaded not guilty. But during police interrogation, he claimed he acted to prevent attacks Atomwaffen members were plotting, and because his roommates were taunting him for his religious conversion.

"In hindsight, it's very stupid what I've done. And honestly, all of this feels very surreal, like a dream," he told police in a videotaped interrogation that was recently released.

Another roommate, Brandon Russell, 22, was considered a leader of Atomwaffen. In a separate case, he was sentenced in January to five years for possessing explosives.

Atomwaffen was also one of the many white supremacist groups that gathered last year in Charlottesville, Va., for a rally that turned violent.

"I've been doing this work for 17 years, and not to be hyperbolic in any way, but we've never been as busy as we are today," said Mendelson, of the ADL. "The white supremacists are much more emboldened."

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