Following the attack on congressional Republicans by a left-wing political activist on Wednesday, VICE News sat down with a few domestic extremism experts to talk about the surge in political violence in the U.S., particularly from the left. In his discussion with the news outlet, Brian Levin, director of the Center for the Study of Hate and Extremism at California State University, issued a chilling warning about "something" he feared was "coalescing on the hard left."

On Wednesday, virulently anti-Republican and anti-Trump Bernie Sanders supporter James T. Hodgkinson unloaded dozens of rounds on a Republican congressional baseball practice, injuring several people, including Rep. Steve Scalise, who has been in critical condition since. While VICE notes that domestic extremism experts caution that it's "not so simple" to blame Hodgkinson's actions on his far-left political leanings, they are seeing a troubling trend among the "hard left." In fact, it's so pronounced that "monitors of right-wing extremism have begun shifting their focus, and sounding the alarm."

Levin told VICE that he began to pay more attention to what was stirring on the radical left in the spring of 2016 when he was documenting a Ku Klux Klan rally in Anaheim that turned violent. After witnessing the "anti-fascist" counter-protesters attack the Klansmen — at one point Levin even putting himself in harm's way to try to protect a Klansman from a violent Anti-Fa member — Levin said he began to think he might have been overlooking the threat posed by the other end of the ideological spectrum.

"At that point, I said we have something coalescing on the hard left," said Levin.

Though VICE notes that so far the evidence is "anecdotal," those keeping an eye on the rise of violence from the far left, like Levin and Washburn University's Chris Hamilton, are seeing disturbing trends:

Levin says that since December 2015, he’s documented nearly two-dozen episodes in California where political events turned violent because of agitation on both sides, something he says he hardly ever saw before. Now, there are violent clashes on college campuses involving groups like Antifa, the anti-fascist group, taking on the alt-right; and aggressive anti-Trump rallies attended by members of the Redneck Revolt, a new pro-minority, anti-supremacist group that encourages its members to train with rifles. Online, hard leftists increasingly discuss politics in dire terms, and rationalize violence as a necessity— even the true inheritor of traditional progressive activism. (Or, in the case of the “Punch a Nazi” meme, a fun game.) ...

Hamilton says that as he browses far-left websites and listens to left-wing talk radio, he hears some of the same sentiments he’s been hearing for years on the right. “These days, that kind of sentiment is popping up in the middle and on the left; it’s not just in the sovereign citizen movement,” he said. “I’m really worried about rising civil strife in the U.S.”

Levin, Hamilton and others, like Center on Extremism's Oren Segal, paint a dire picture of the political landscape.

"When we have anti-fascist counterprotests — not that they are the same as white supremacists — that can ratchet up the violence at these events, and it means we can see people who are violent on their own be attracted to that," said Segal. "I hate to say it, but it feels inevitable."

Despite all the obvious warning signs, however, Levin said that his attempts so far to appeal to authorities about this "democratization of extremism" have gone unheeded.

"I've been going up and down the state of California meeting with law enforcement officials about this," said Levin. "I'm very concerned about it. What we're seeing is the democratization of extremism and the tactics of radicalism. I’ve been warning about this, and nobody gave a sh*t."