Rabbi David Locketz has felt the sting of bigotry in his career, and even a death threat via Facebook last year.

But a recent wave of anti-Semitic incidents, including two bomb threats in the Twin Cities in the last five weeks, has struck a frightening and ugly chord that feels new to him.

"Our experience as a community in this country has never been that we have had to worry about an organized threat," said Locketz, senior rabbi for the Bet Shalom congregation in Minnetonka. "That's what has been unique about the last several weeks: It feels so organized and so massive."

Minnesota is in the midst of a startling rise in anti-Semitic incidents, a chilling surge that started even before the two bomb threats phoned in to the Jewish community centers in St. Paul and St. Louis Park. Law enforcement records show 11 hate crimes against Jews reported in Minnesota in 2016 — a three-year high. The local Jewish Community Relations Council (JCRC), which compiles its own list, also tallied a surge in hate incidents — 21 reports last year, up from 12 in 2015. And this year's count is on pace to be even higher. Authorities across the country are reporting a similar spike in such threats.

In response, the FBI and other federal officials have ramped up their engagement with local JCCs, advising them on security measures and encouraging them to report any suspected hate crimes. Local police have increased patrols around Twin Cities synagogues during weekly services. And U.S. Attorney Andrew Luger, the top federal prosecutor in Minnesota, said his office is participating in a nationwide investigation into the recent bomb scares, which he called part of a "different and heightened" climate of concern.

"This threat has rocked our whole community to the core," said Soni Cohen of the Sabes JCC in St. Louis Park, which had to evacuate nearly 500 people after a Jan. 18 bomb threat. "Because it's no longer just a drill."

Authorities have been unable to pinpoint a single inspiration behind the latest hate incidents in Minnesota.

But the actions of one young Minneapolis perpetrator, documented by the Star Tribune through his online activity, helps pull back the curtain on the spreading influence of white supremacist networks.

Shortly after plastering the University of Minnesota campus with swastika-studded fliers earlier this month, the young man logged in online and accepted an invitation to join the local chapter of a popular white supremacist website called the Daily Stormer. Behind the anonymity of his web profile, he celebrated with his newfound digital brotherhood:

"I did it for all of you," he wrote on a forum of the site, whose users reportedly have included Dylann Roof, the man who in 2015 killed nine black parishioners at a South Carolina church. "I never imagined that there were so many great racists and fine upstanding Nazis."

Throughout the weekend, the young man, identified only by the username "Whitelash," disclosed that he had "virtually no family" and "so little to lose." Unemployed and "partially disabled," he said he struggled to find the $6 to print the fliers and pay for a light-rail train to campus from his home near the airport. He promised "future exploits" and boasted that he didn't fear punishment: "If I lose, I'll be like a martyr for our cause."

In an earlier thread related to an FBI investigation in South Carolina, "Whitelash" wrote: "Some day, when we are the authorities, we can purge our enemies with impunity."

Tony McAleer, a former skinhead from Canada who now helps run a nonprofit aimed at reforming extremists, said the young man's behavior signaled a troubled quest for belonging familiar to many who wind up in white supremacist circles.

"There are probably thousands of guys like him," said McAleer, executive director of the Chicago-based Life After Hate. "When you scratch below the surface you find similar kinds of stories: Someone who doesn't quite fit in, looking for their place in the world. They can't find it in a mainstream way, but with very little effort he can make himself a hero by putting fliers on campus."

For the Twin Cities JCCs, the recent bomb threats represented a new test of existing security protocols, said Steve Hunegs, executive director of the JCRC, the public advocacy voice of the Twin Cities Jewish community. At the Sabes JCC in St. Louis Park last month, staff shuttled all 500 of its visitors to a warm, secure location and was back in operation the next day. The St. Paul JCC, meanwhile, was able to reopen its doors just hours after its scare last week.

"That's a strong expression — a strong response to acts of intimidation," Hunegs said.

The incidents triggered increased law enforcement activity around Twin Cities Jewish institutions, and some families were left wondering if they can safely leave their children at day care or school.

Still, local faith leaders said they're hopeful that supportive ecumenical and community responses have calmed families' fears.

"Nobody has said to me that they aren't coming because they're scared," Locketz said.

In fact, many in the Jewish community suggest the subsequent show of community support has outweighed the hateful acts. Cohen said the Sabes JCC received a letter signed by 252 faith leaders expressing solidarity, and students from a nearby Catholic school created a mural for the children at Sabes. And on Friday, 22 Muslim organizations signed a half-page Star Tribune ad that called the recent hate acts an affront "against all people and the values we hold as Americans."

"That is so important," Cohen said, "because it's easy to start to believe that everybody hates you."

Next month, Temple Israel in Minneapolis will host a forum featuring Christian Picciolini, a former Nazi skinhead who founded Life After Hate. Picciolini, who lives in Chicago, said he considered the Twin Cities a second home during his days in the movement 25 years ago. He still holds out hope that his St. Paul friends, whom he called good people, will find a way out.

"Most people, regardless if they [are] white extremists or jihadists, become radicalized secondarily to a search for identity, community and purpose," Picciolini said. "The ideology is just the tie that binds."

Picciolini and McAleer are among those concerned by reports that the Trump administration plans to refocus federal counter-extremism policies narrowly on Islamic radicals. Among other things, that would imperil a $400,000 grant Life After Hate was selected to receive for anti-Nazi work from the Department of Homeland Security.

In the shared vigilance and interfaith gestures that have sprung up across the Twin Cities, rabbis like Locketz say they see opportunities to forge alliances. Even though Locketz's congregation wasn't targeted in the recent hate incidents, he said a Plymouth Islamic center planned to present a gift at Saturday's Shabbat service.

Citing that gesture, Locketz invoked a metaphor from the Torah.

"One of the real negatives of anti-Semitism is what feels like isolation," Locketz said. "Here we are living in a place, and all of a sudden you don't know who you trust. To have that isolation removed … because we have so many close friends expressing support for us — that's what brings light into dark places."

Stephen Montemayor • 612-673-1755

Twitter: @smontemayor