Updated

The friendship of the four young roommates — though cemented in the dark trappings of an obscure neo-Nazi group called Atomwaffen Division — never seemed destined for bloodshed.

One was described as a former science nerd, serving in the Florida National Guard. Two others worked temp jobs at a recycling plant and talked about joining the military. The fourth caught flak from his roommates for wasting his days with video games.

Now two of the young men are dead, the other two are in jail and authorities are left to answer this question: Was Atomwaffen Division plotting violent acts or were the four young men merely posers?

Four days after police say one of the roommates shot and killed two others, Atomwaffen posted an ominous video on YouTube depicting members standing with arms extended in "Heil Hitler" salutes and posing with guns in front of a swastika flag, their faces obscured by images of skulls. It ended with a stark slogan, scrawled in red: "Join your local Nazis."

Inside the apartment the men shared, authorities said they found guns, ammunition and bomb-making material, along with a framed picture of Oklahoma City bomber Timothy McVeigh on a bedroom dresser.

After his arrest in May on murder charges, Devon Arthurs, the group's 18-year-old co-founder, told police detectives that he killed his roommates to thwart a terrorist attack by Atomwaffen, which is German for "atomic weapon."

"I prevented the deaths of a lot of people," Arthurs said in a rambling statement. Asked why his roommates would plan such an attack, he responded, "Because they want to build a Fourth Reich."

The victims' families insist, however, that the two slain young men were moving on to new phases in their lives. And another Atomwaffen member characterizes the group as simply a band of trolls who delight in provoking outrage with stunts like picketing at a vigil for victims of the Orlando nightclub shooting and posting racist flyers on college campuses.

"I'm a neo-Nazi. I'm not a monster," 20-year-old William Tschantre told The Associated Press.

Atomwaffen doesn't have near the numbers or the notoriety of some of the white nationalist and neo-Nazi groups that gathered in Charlottesville, Virginia, for the rally that led to deadly clashes. Tschantre and others estimate that it has only a few dozen members nationwide.

But federal investigators say they believe the May 19 shooting exposed disturbing evidence of a credible threat to the public. In the condo's garage, they say, bomb-squad technicians found volatile explosive material stored in a cooler, near homemade detonator components and several pounds of ammonium nitrate. Two sources of radiation also were detected on the premises, they say.

FBI agents have filed explosives charges against Atomwaffen's leader, 21-year-old Brandon Russell, who was dressed in a military uniform and crying outside the apartment when Arthurs led officers to the grisly scene. Arthurs said Russell, who had just returned home from his Florida National Guard duties, knew nothing about the killings. But he accused Russell of stockpiling explosives to bomb power lines, nuclear reactors and synagogues.

After seeing pictures of the bomb-making materials and firearms in Russell's possession, a federal judge agreed he posed a risk to the public and ordered him detained. The judge added, however, that he was troubled investigators hadn't presented more evidence to corroborate Arthurs' claims about Atomwaffen, such as his assertion that Russell threatened violence in online chats.

Arthurs' accusations against his slain roommates — 18-year-old Andrew Oneschuk and 22-year-old Jeremy Himmelman, leader of Atomwaffen's Massachusetts branch — have angered their grieving relatives. Their families dismiss his claims as the self-serving rantings of a sociopath who initially told investigators that he killed his friends for teasing him about his recent conversion to Islam.

Tschantre, who was at Russell's side when FBI agents arrested him, also scoffs at Arthurs' portrayal of Atomwaffen as a terrorist group.

"We're not here to, like, bomb the U.S. government," Tschantre said. "That's absolutely ridiculous."

___

In anonymous internet posts, Atomwaffen members hailed Oneschuk and Himmelman as fallen heroes and assailed Arthurs as a race traitor. A tribute on IronMarch, a website for the "global fascist fraternity," included swastika-stamped photos of the slain men.

Relatives and friends of Oneschuk and Himmelman reject any neo-Nazi labels, but do not dispute that they shared an internet-fueled interest in right-wing ideologies.

Kianna Kaizer, Himmelman's girlfriend, called his "political side" only a small part of his life but acknowledged he held decidedly far-right beliefs.

"Jeremy went through a lot of struggle in his life, and national socialism offered him the rigidity he desired, and offered him solutions for the things out of his control," Kaizer wrote in an email. "So it's been really hard to try and tell his family, but yes he did hold white supremacist beliefs and national socialist beliefs."

Himmelman's mother herself alluded to her son's interest in right-wing politics in a Facebook post after his death.

Walter Oneschuk said he had confronted his son when he was younger about seeking out "ultra-right-wing conservative" material and, when Andrew was 15, blocked his computer from accessing sites rife with racist and anti-Semitic content.

Andrew Oneschuk didn't drink, abhorred drugs and never fit in at the prep schools he attended or the liberal arts college he left after one semester, his father said.

"Andrew was a very conservative guy," Walter Oneschuk said. "He looked at his generation and said, 'We're on the path to ruin.'"

Last November, six months shy of turning 18, Andrew traveled to France and joined the French Foreign Legion, a force of volunteer soldiers from around the world, to test his mettle with "old-school soldiering," his father said. But his stint didn't even last a month; his father said he faked a shoulder injury to escape service.

Oneschuk said his son's fervor for far-right extremism waned after his return from France.

"He was a different kid when he came back," he said. "He realized this stuff was not his future."

Walter Oneschuk believes his son met Himmelman and Arthurs online last year, and Kaizer said Himmelman introduced Andrew Oneschuk to her as an Atomwaffen member. She said it was Russell who appointed her boyfriend as the group's leader in Massachusetts.

It was the lure of a rent-free home and the prospect of bountiful fishing that convinced Himmelman and Oneschuk to leave Massachusetts and spend part of the summer in Florida, where Russell and Arthurs were living in a two-story condo.

Himmelman was in a financial rut and open to a fresh start when Russell began pressuring him to move to Tampa, friends and family said. He had toyed with joining the military, they said, but instead planned to use his Florida experience to figure out his next move.

And Andrew Oneschuk's father said his son had met with a Navy recruiter in April, on his 18th birthday, and looked forward to starting a military career.

Once the pair arrived in Florida, tensions between the roommates quickly mounted. Kaizer said Himmelman and Oneschuk often teased Arthurs for having no job and spending most of his time playing video games.

"Jeremy went down there expecting a break from the stress he was under in Massachusetts," she said. "As soon as Jeremy arrived in Florida, the stark difference between the promises made and reality were apparent."

Oneschuk was ready to leave soon after their arrival. He told his father he was the only one who cooked or cleaned and that he was tired of Arthurs' attempts to convert him to Islam.

Arthurs' religious rhetoric also annoyed other Atomwaffen members, according to Tschantre. On May 18, the night before the shooting, Arthurs argued with group members about his conversion during a private online chat, Tschantre said.

"I told them to calm down," he said.

Himmelman and Oneschuk didn't join in the chat, but Tschantre said he suspects the heated exchange could explain how Arthurs' anger turned into violence the next evening.

Two days before the shooting, Walter Oneschuk said, Andrew had called to say he was coming home after less than two weeks in Florida. He was eagerly awaiting his son's arrival when he heard a knock on the door of his suburban Boston home: Two police officers told him Andrew was dead.

The retired Navy pilot traveled to Tampa to retrieve his son's belongings, including an American flag he had acquired during an overseas deployment and given to his son.

"He had hung it up in the apartment," Oneschuk said, his voice cracking.

Himmelman's girlfriend and his sister, Lyssa, said he had complained that Arthurs and Russell were pulling down the flag and stomping on it. It infuriated Jeremy and Andrew, they said.

___

The morning after the shooting, Russell had not yet been arrested. He was still wearing military fatigues when he knocked on Tschantre's door in Bradenton and broke the news of the killings.

"I could tell by the look on his face he wasn't joking," Tschantre said. "He was on the verge of tears."

Tschantre grabbed about $3,000 in cash and quit his job at a fast-food restaurant as they left town. They initially planned to visit Russell's father, a sheriff's deputy who lives in West Palm Beach, but decided instead to camp in the Florida Keys, Tschantre said.

"He knew his dad would get really mad," he said.

They stopped at a sporting goods store and bought two rifles and about 500 rounds of ammunition, which Tschantre said they wanted in case they went hunting, though he initially told authorities the guns were for self-defense. Prosecutors noted it wasn't hunting season anywhere at the time.

The friends crashed at a hotel near Miami that night. The next morning, sheriff's deputies arrested Russell about 60 miles away, at a Burger King in Key Largo. Investigators found a skull mask along with the rifles in Russell's car.

When investigators questioned Russell about the explosives found at the apartment, he said he had joined an engineering club in college and used the material to boost homemade rockets.

Friends described Russell as a science nerd. In a YouTube video with 3.6 million views since its posting in March, he had helped Kevin Kohler, the host of "The Backyard Scientist," use an electrical charge to blow a hole in a slab of raw meat.

Kohler described Russell as a socially awkward introvert when they met at the University of South Florida in Tampa. When he saw news reports that investigators had detected radiation in Russell's apartment, he recalled seeing a Geiger counter for sale at an electronics festival during their college days and Russell telling him he already had one or two.

"He knew a lot about Atomic-era stuff," Kohler said.

He added that he never suspected Russell was in a hate group.

In a 2015 post on IronMarch under his screen name, Russell had described Atomwaffen as a "fanatical, ideological band of comrades who do both activism and militant training."

"Keyboard warriorism is nothing to do with what we are," he wrote.

___

Kunzelman reported from Baton Rouge, Louisiana.