Just two days ago, James Hodgkinson opened fired on dozens of Republican congressmen and staffers at a baseball practice in Alexandria, Virginia. The shooting has raised serious concerns among extremism experts regarding leftist extremism in the United States.

In the past few months, extremist experts have seen a rise in politically motivated violence from the far left, Vice News reports. As of late, there have been a multitude of violent acts from the far left including Antifa violence at U.C. Berkley and the riots in D.C. following Donald Trump’s inauguration.

Ever since the 2016 presidential election, the American Defamation League (ADL) has been tracking the growing anger within the American left, specifically directed at President Trump and his administration. According to Oren Segal, the Director of ADL’s Center on Extremism, the “ADL has been warning law enforcement personnel about the possibility of an increase in left-wing violence as a result of growing anger. The shootings in Alexandria appear to be an example of this.”

However, Segal is not the only extremism expert that acknowledges the left-wing violence. Brian Levin, a professor in the Department of Criminal Justice at the California State University at San Bernardino, former NYPD Officer and self proclaimed free speech enthusiast, has also echoed this sentiment. Levin has been warning of leftist extremism for quite some time now and points out that it goes back to the early 1970’s.

In an interview with The Daily Caller, Levin reiterated that the “left has coalesced into a small, disorganized movement” and that “the violence is not indigenous to just one side of the political spectrum.” Still, he says it is a movement we need to monitor.

“We’re facing the most diverse threat matrix we have had in decades” and “the hard left is small but it’s on the map now which should be concerning to everyone,” Levin told TheDC.

Levin stated that “we have to get out of the “gotcha” game” when it comes naming which ideological spectrum the violence comes from. But Levin acknowledged that ideology is not irrelevant. He argues that the one thing that all extremist groups in America have in common is that they are “anti-establishment” and have “opted out of democracy,” he told TheDC.